diff --git a/src/connector/src/aws_utils.rs b/src/connector/src/aws_utils.rs
index 1578c7b844422..5bf373baa647b 100644
--- a/src/connector/src/aws_utils.rs
+++ b/src/connector/src/aws_utils.rs
@@ -15,7 +15,7 @@
 use std::collections::HashMap;
 use std::time::Duration;
 
-use anyhow::Context;
+use anyhow::{anyhow, Context};
 use aws_config::timeout::TimeoutConfig;
 use aws_sdk_s3::{client as s3_client, config as s3_config};
 use url::Url;
@@ -111,13 +111,15 @@ pub async fn load_file_descriptor_from_s3(
     let bucket = location
         .domain()
         .with_context(|| format!("illegal file path {}", location))?;
-    let key = location.path().replace('/', "");
+    let key = location.path().strip_prefix('/').ok_or(anyhow!(
+        "s3 url {location} should have a '/' at the start of path."
+    ))?;
     let sdk_config = config.build_config().await?;
     let s3_client = s3_client(&sdk_config, Some(default_conn_config()));
     let response = s3_client
         .get_object()
         .bucket(bucket.to_string())
-        .key(&key)
+        .key(key)
         .send()
         .await
         .with_context(|| format!("failed to get file from s3 at `{}`", location))?;