diff --git a/atomic_reactor/tasks/binary_container_build.py b/atomic_reactor/tasks/binary_container_build.py
index 9a1445b55..282c27f6c 100644
--- a/atomic_reactor/tasks/binary_container_build.py
+++ b/atomic_reactor/tasks/binary_container_build.py
@@ -257,6 +257,8 @@ def build_container(
             f"--tag={dest_tag}",
             "--no-cache",  # make sure the build uses a clean environment
             "--pull-always",  # as above
+            # ensure that Dockerfile is always used even when Containerfile exists
+            "--file=Dockerfile",
         ]
         if memory_limit:
             # memory limit (format: <number>[<unit>], where unit = b, k, m or g)
diff --git a/tests/tasks/test_binary_container_build.py b/tests/tasks/test_binary_container_build.py
index 4ced4a4cd..11839cfaf 100644
--- a/tests/tasks/test_binary_container_build.py
+++ b/tests/tasks/test_binary_container_build.py
@@ -473,6 +473,7 @@ def test_build_container(self, authfile, is_flatpak, x86_build_dir, memory_limit
             f"--tag={X86_UNIQUE_IMAGE}",
             "--no-cache",
             "--pull-always",
+            "--file=Dockerfile",
         ]
         if memory_limit:
             options.append(f"--memory={memory_limit}")