diff --git a/src/meta/service/src/configs/outer_v0.rs b/src/meta/service/src/configs/outer_v0.rs
index 0a9111529b19f..a37c47face166 100644
--- a/src/meta/service/src/configs/outer_v0.rs
+++ b/src/meta/service/src/configs/outer_v0.rs
@@ -760,7 +760,7 @@ pub struct FileLogConfig {
 
     /// Log file max size, default is 4GB
     #[clap(long = "log-file-max-size", default_value = "4294967296")]
-    #[serde(rename = "max-size")]
+    #[serde(rename = "max_size")]
     pub file_max_size: usize,
 
     /// Deprecated fields, used for catching error, will be removed later.
diff --git a/src/query/config/src/config.rs b/src/query/config/src/config.rs
index f5cd008746e83..6f9ae6c1284b0 100644
--- a/src/query/config/src/config.rs
+++ b/src/query/config/src/config.rs
@@ -2413,7 +2413,7 @@ pub struct FileLogConfig {
         value_name = "VALUE",
         default_value = "4294967296"
     )]
-    #[serde(rename = "max-size")]
+    #[serde(rename = "max_size")]
     pub file_max_size: usize,
 
     /// Deprecated fields, used for catching error, will be removed later.
diff --git a/src/query/service/tests/it/storages/testdata/configs_table_basic.txt b/src/query/service/tests/it/storages/testdata/configs_table_basic.txt
index 3ef82918b82a9..01633f755ae6c 100644
--- a/src/query/service/tests/it/storages/testdata/configs_table_basic.txt
+++ b/src/query/service/tests/it/storages/testdata/configs_table_basic.txt
@@ -41,7 +41,7 @@ DB.Table: 'system'.'configs', Table: configs-table_id:1, ver:0, Engine: SystemCo
 | 'log'     | 'file.format'                                        | 'text'                                                                                                                                                                                                    | ''       |
 | 'log'     | 'file.level'                                         | 'WARN,databend=DEBUG,openraft=DEBUG'                                                                                                                                                                      | ''       |
 | 'log'     | 'file.limit'                                         | '48'                                                                                                                                                                                                      | ''       |
-| 'log'     | 'file.max-size'                                      | '4294967296'                                                                                                                                                                                              | ''       |
+| 'log'     | 'file.max_size'                                      | '4294967296'                                                                                                                                                                                              | ''       |
 | 'log'     | 'file.on'                                            | 'true'                                                                                                                                                                                                    | ''       |
 | 'log'     | 'file.prefix_filter'                                 | 'null'                                                                                                                                                                                                    | ''       |
 | 'log'     | 'history.interval'                                   | '2'                                                                                                                                                                                                       | ''       |