diff --git a/README.md b/README.md
index 72add83..d7ecde3 100644
--- a/README.md
+++ b/README.md
@@ -49,6 +49,49 @@ func main() {
 	e.SavePolicy()
 }
 ```
+## Advanced Example
+
+```go
+package main
+
+import (
+	"github.com/casbin/casbin/v2"
+	"github.com/casbin/mongodb-adapter/v3"
+	mongooptions "go.mongodb.org/mongo-driver/mongo/options"
+)
+
+func main() {
+	// Initialize a MongoDB adapter with NewAdapterWithClientOption:
+	// The adapter will use custom mongo client options.
+	// custom database name.
+	// default collection name 'casbin_rule'.
+	mongoClientOption := mongooptions.Client().ApplyURI("mongodb://127.0.0.1:27017")
+	databaseName := "casbin"
+	a,err := mongodbadapter.NewAdapterWithClientOption(mongoClientOption, databaseName)
+	// Or you can use NewAdapterWithCollectionName for custom collection name.
+	if err != nil {
+		panic(err)
+	}
+
+	e, err := casbin.NewEnforcer("examples/rbac_model.conf", a)
+	if err != nil {
+		panic(err)
+	}
+
+	// Load the policy from DB.
+	e.LoadPolicy()
+	
+	// Check the permission.
+	e.Enforce("alice", "data1", "read")
+	
+	// Modify the policy.
+	// e.AddPolicy(...)
+	// e.RemovePolicy(...)
+	
+	// Save the policy back to DB.
+	e.SavePolicy()
+}
+```
 
 ## Filtered Policies
 
diff --git a/adapter.go b/adapter.go
index 510d0eb..f2e7e31 100644
--- a/adapter.go
+++ b/adapter.go
@@ -32,6 +32,8 @@ import (
 )
 
 const defaultTimeout time.Duration = 30 * time.Second
+const defaultDatabaseName string = "casbin"
+const defaultCollectionName string = "casbin_rule"
 
 // CasbinRule represents a rule in Casbin.
 type CasbinRule struct {
@@ -60,6 +62,7 @@ func finalizer(a *adapter) {
 
 // NewAdapter is the constructor for Adapter. If database name is not provided
 // in the Mongo URL, 'casbin' will be used as database name.
+// 'casbin_rule' will be used as a collection name.
 func NewAdapter(url string, timeout ...interface{}) (persist.BatchAdapter, error) {
 	if !strings.HasPrefix(url, "mongodb+srv://") && !strings.HasPrefix(url, "mongodb://") {
 		url = fmt.Sprint("mongodb://" + url)
@@ -79,15 +82,26 @@ func NewAdapter(url string, timeout ...interface{}) (persist.BatchAdapter, error
 	if connString.Database != "" {
 		databaseName = connString.Database
 	} else {
-		databaseName = "casbin_rule"
+		databaseName = defaultDatabaseName
 	}
 
-	return NewAdapterWithClientOption(clientOption, databaseName, timeout...)
+	return baseNewAdapter(clientOption, databaseName, defaultCollectionName, timeout...)
 }
 
 // NewAdapterWithClientOption is an alternative constructor for Adapter
-// that does the same as NewAdapter, but uses mongo.ClientOption instead of a Mongo URL
+// that does the same as NewAdapter, but uses mongo.ClientOption instead of a Mongo URL + a databaseName option
 func NewAdapterWithClientOption(clientOption *options.ClientOptions, databaseName string, timeout ...interface{}) (persist.BatchAdapter, error) {
+	return baseNewAdapter(clientOption, databaseName, defaultCollectionName, timeout...)
+}
+
+// NewAdapterWithCollectionName is an alternative constructor for Adapter
+// that does the same as NewAdapterWithClientOption, but with an extra collectionName option
+func NewAdapterWithCollectionName(clientOption *options.ClientOptions, databaseName string, collectionName string, timeout ...interface{}) (persist.BatchAdapter, error) {
+	return baseNewAdapter(clientOption, databaseName, collectionName, timeout...)
+}
+
+// baseNewAdapter is a base constructor for Adapter
+func baseNewAdapter(clientOption *options.ClientOptions, databaseName string, collectionName string, timeout ...interface{}) (persist.BatchAdapter, error) {
 	a := &adapter{
 		clientOption: clientOption,
 	}
@@ -102,7 +116,7 @@ func NewAdapterWithClientOption(clientOption *options.ClientOptions, databaseNam
 	}
 
 	// Open the DB, create it if not existed.
-	err := a.open(databaseName)
+	err := a.open(databaseName, collectionName)
 	if err != nil {
 		return nil, err
 	}
@@ -125,7 +139,7 @@ func NewFilteredAdapter(url string) (persist.FilteredAdapter, error) {
 	return a.(*adapter), nil
 }
 
-func (a *adapter) open(databaseName string) error {
+func (a *adapter) open(databaseName string, collectionName string) error {
 	ctx, cancel := context.WithTimeout(context.TODO(), a.timeout)
 	defer cancel()
 
@@ -135,7 +149,7 @@ func (a *adapter) open(databaseName string) error {
 	}
 
 	db := client.Database(databaseName)
-	collection := db.Collection("casbin_rule")
+	collection := db.Collection(collectionName)
 
 	a.client = client
 	a.collection = collection
diff --git a/adapter_test.go b/adapter_test.go
index 065a6a6..7fad8c6 100644
--- a/adapter_test.go
+++ b/adapter_test.go
@@ -17,11 +17,13 @@ package mongodbadapter
 import (
 	"fmt"
 	"os"
+	"strings"
 	"testing"
 
 	"github.com/casbin/casbin/v2"
 	"github.com/casbin/casbin/v2/util"
 	"go.mongodb.org/mongo-driver/bson"
+	mongooptions "go.mongodb.org/mongo-driver/mongo/options"
 )
 
 var testDbURL = os.Getenv("TEST_MONGODB_URL")
@@ -104,7 +106,7 @@ func TestAdapter(t *testing.T) {
 		{"bob", "data2", "write"},
 		{"data2_admin", "data2", "read"},
 		{"data2_admin", "data2", "write"},
-		},
+	},
 	)
 	// AutoSave is enabled by default.
 	// Now we disable it.
@@ -122,7 +124,7 @@ func TestAdapter(t *testing.T) {
 		{"bob", "data2", "write"},
 		{"data2_admin", "data2", "read"},
 		{"data2_admin", "data2", "write"},
-		},
+	},
 	)
 
 	// Now we enable the AutoSave.
@@ -142,8 +144,8 @@ func TestAdapter(t *testing.T) {
 		{"data2_admin", "data2", "read"},
 		{"data2_admin", "data2", "write"},
 		{"alice", "data1", "write"},
-		},
-	)	
+	},
+	)
 
 	// Remove the added rule.
 	e.RemovePolicy("alice", "data1", "write")
@@ -158,7 +160,7 @@ func TestAdapter(t *testing.T) {
 		{"bob", "data2", "write"},
 		{"data2_admin", "data2", "read"},
 		{"data2_admin", "data2", "write"},
-		},
+	},
 	)
 
 	// Remove "data2_admin" related policy rules via a filter.
@@ -170,7 +172,7 @@ func TestAdapter(t *testing.T) {
 	testGetPolicy(t, e, [][]string{
 		{"alice", "data1", "read"},
 		{"bob", "data2", "write"},
-		},
+	},
 	)
 
 	e.RemoveFilteredPolicy(1, "data1")
@@ -204,15 +206,15 @@ func TestAddPolicies(t *testing.T) {
 		{"bob", "data2", "write"},
 		{"data2_admin", "data2", "read"},
 		{"data2_admin", "data2", "write"},
-		},
+	},
 	)
-	a.AddPolicies("p","p",[][]string{
+	a.AddPolicies("p", "p", [][]string{
 		{"bob", "data2", "read"},
 		{"alice", "data2", "write"},
 		{"alice", "data2", "read"},
 		{"bob", "data1", "write"},
 		{"bob", "data1", "read"},
-		},
+	},
 	)
 
 	if err := e.LoadPolicy(); err != nil {
@@ -222,14 +224,14 @@ func TestAddPolicies(t *testing.T) {
 	testGetPolicy(t, e, [][]string{
 		{"alice", "data1", "read"},
 		{"bob", "data2", "write"},
-		{"data2_admin", "data2", "read"}, 
+		{"data2_admin", "data2", "read"},
 		{"data2_admin", "data2", "write"},
 		{"bob", "data2", "read"},
 		{"alice", "data2", "write"},
 		{"alice", "data2", "read"},
 		{"bob", "data1", "write"},
 		{"bob", "data1", "read"},
-		},
+	},
 	)
 
 	// Remove the added rule.
@@ -248,10 +250,10 @@ func TestAddPolicies(t *testing.T) {
 	testGetPolicy(t, e, [][]string{
 		{"alice", "data1", "read"},
 		{"bob", "data2", "write"},
-		{"data2_admin", "data2", "read"}, 
+		{"data2_admin", "data2", "read"},
 		{"data2_admin", "data2", "write"},
-		},
-		)
+	},
+	)
 }
 
 func TestDeleteFilteredAdapter(t *testing.T) {
@@ -322,7 +324,7 @@ func TestFilteredAdapter(t *testing.T) {
 	if err != nil {
 		panic(err)
 	}
-	
+
 	// Load filtered policies from the database.
 	e.AddPolicy("alice", "data1", "write")
 	e.AddPolicy("bob", "data2", "write")
@@ -343,7 +345,7 @@ func TestFilteredAdapter(t *testing.T) {
 	testGetPolicy(t, e, [][]string{
 		{"alice", "data1", "read"},
 		{"alice", "data1", "write"},
-		},
+	},
 	)
 
 	// Test safe handling of SavePolicy when using filtered policies.
@@ -400,3 +402,30 @@ func TestNewAdapterWithDatabase(t *testing.T) {
 		panic(err)
 	}
 }
+
+func TestNewAdapterWithClientOption(t *testing.T) {
+	uri := getDbURL()
+	if !strings.HasPrefix(uri, "mongodb+srv://") && !strings.HasPrefix(uri, "mongodb://") {
+		uri = fmt.Sprint("mongodb://" + uri)
+	}
+	mongoClientOption := mongooptions.Client().ApplyURI(uri)
+	databaseName := "casbin_custom"
+	_, err := NewAdapterWithClientOption(mongoClientOption, databaseName)
+	if err != nil {
+		panic(err)
+	}
+}
+
+func TestNewAdapterWithCollectionName(t *testing.T) {
+	uri := getDbURL()
+	if !strings.HasPrefix(uri, "mongodb+srv://") && !strings.HasPrefix(uri, "mongodb://") {
+		uri = fmt.Sprint("mongodb://" + uri)
+	}
+	mongoClientOption := mongooptions.Client().ApplyURI(uri)
+	databaseName := "casbin_custom"
+	collectionName := "casbin_rule_custom"
+	_, err := NewAdapterWithCollectionName(mongoClientOption, databaseName, collectionName)
+	if err != nil {
+		panic(err)
+	}
+}