diff --git a/src/connector/src/source/pulsar/mod.rs b/src/connector/src/source/pulsar/mod.rs
index c9db87fd3bb94..5a1d73963bd23 100644
--- a/src/connector/src/source/pulsar/mod.rs
+++ b/src/connector/src/source/pulsar/mod.rs
@@ -49,8 +49,8 @@ pub struct PulsarProperties {
     pub common: PulsarCommon,
 
     #[serde(rename = "iceberg.enabled")]
-    #[serde_as(as = "Option<DisplayFromStr>")]
-    pub iceberg_loader_enabled: bool,
+    #[serde_as(as = "DisplayFromStr")]
+    pub iceberg_loader_enabled: Option<bool>,
 
     #[serde(rename = "iceberg.bucket", default)]
     pub iceberg_bucket: Option<String>,
diff --git a/src/connector/src/source/pulsar/source/reader.rs b/src/connector/src/source/pulsar/source/reader.rs
index 0568a8935932e..04fee26f42aa7 100644
--- a/src/connector/src/source/pulsar/source/reader.rs
+++ b/src/connector/src/source/pulsar/source/reader.rs
@@ -65,7 +65,7 @@ impl SplitReader for PulsarSplitReader {
 
         tracing::debug!("creating consumer for pulsar split topic {}", topic,);
 
-        if props.iceberg_loader_enabled
+        if props.iceberg_loader_enabled.unwrap_or(false)
             && matches!(split.start_offset, PulsarEnumeratorOffset::Earliest)
             && !topic.starts_with("non-persistent://")
         {