diff --git a/R/wb_load.R b/R/wb_load.R
index 60a254823..a29d04c67 100644
--- a/R/wb_load.R
+++ b/R/wb_load.R
@@ -368,7 +368,7 @@ wb_load <- function(
       } else if (sheets$typ[i] == "worksheet") {
         content_type <- read_xml(ContentTypesXML)
         override <- xml_attr(content_type, "Types", "Override")
-        overrideAttr <- as.data.frame(do.call("rbind", override))
+        overrideAttr <- as.data.frame(do.call("rbind", override), stringsAsFactors = FALSE)
         xmls <- basename(unlist(overrideAttr$PartName))
         drawings <- grep("drawing", xmls, value = TRUE)
         wb$add_worksheet(sheets$name[i], visible = is_visible[i], has_drawing = !is.na(drawings[i]))