diff --git a/src/s3/response/list_objects.rs b/src/s3/response/list_objects.rs
index 043c3994..5fd4696f 100644
--- a/src/s3/response/list_objects.rs
+++ b/src/s3/response/list_objects.rs
@@ -99,9 +99,9 @@ fn parse_list_objects_contents(
             &content.get_child_text_or_error("LastModified")?,
         )?);
         let etag = content.get_child_text("ETag");
-        let size: Option<usize> = content
+        let size: Option<u64> = content
             .get_child_text("Size")
-            .map(|x| x.parse::<usize>())
+            .map(|x| x.parse::<u64>())
             .transpose()?;
         let storage_class = content.get_child_text("StorageClass");
         let is_latest = content
diff --git a/src/s3/types.rs b/src/s3/types.rs
index 352eac8f..357e886d 100644
--- a/src/s3/types.rs
+++ b/src/s3/types.rs
@@ -155,7 +155,7 @@ pub struct ListEntry {
     pub etag: Option<String>, // except DeleteMarker
     pub owner_id: Option<String>,
     pub owner_name: Option<String>,
-    pub size: Option<usize>, // except DeleteMarker
+    pub size: Option<u64>, // except DeleteMarker
     pub storage_class: Option<String>,
     pub is_latest: bool,            // except ListObjects V1/V2
     pub version_id: Option<String>, // except ListObjects V1/V2