diff --git a/pyiceberg/manifest.py b/pyiceberg/manifest.py
index 649840fc66..233e5b4d10 100644
--- a/pyiceberg/manifest.py
+++ b/pyiceberg/manifest.py
@@ -93,9 +93,16 @@ def __repr__(self) -> str:
 
 
 class FileFormat(str, Enum):
-    AVRO = "AVRO"
-    PARQUET = "PARQUET"
-    ORC = "ORC"
+    AVRO = "AVRO", "avro"
+    PARQUET = "PARQUET", "parquet"
+    ORC = "ORC", "orc"
+
+    def __new__(cls, value: str, *value_aliases: List[str]) -> "FileFormat":
+        obj = str.__new__(cls)
+        obj._value_ = value
+        for alias in value_aliases:
+            cls._value2member_map_[alias] = obj
+        return obj
 
     def __repr__(self) -> str:
         """Return the string representation of the FileFormat class."""