diff --git a/tuic-server/src/config.rs b/tuic-server/src/config.rs
index de01b6c..9d0deea 100644
--- a/tuic-server/src/config.rs
+++ b/tuic-server/src/config.rs
@@ -39,15 +39,27 @@ pub struct Config {
     #[serde(default = "default::zero_rtt_handshake")]
     pub zero_rtt_handshake: bool,
     pub dual_stack: Option<bool>,
-    #[serde(default = "default::auth_timeout")]
+    #[serde(
+        default = "default::auth_timeout",
+        deserialize_with = "deserialize_duration"
+    )]
     pub auth_timeout: Duration,
-    #[serde(default = "default::max_idle_time")]
+    #[serde(
+        default = "default::max_idle_time",
+        deserialize_with = "deserialize_duration"
+    )]
     pub max_idle_time: Duration,
     #[serde(default = "default::max_external_packet_size")]
     pub max_external_packet_size: usize,
-    #[serde(default = "default::gc_interval")]
+    #[serde(
+        default = "default::gc_interval",
+        deserialize_with = "deserialize_duration"
+    )]
     pub gc_interval: Duration,
-    #[serde(default = "default::gc_lifetime")]
+    #[serde(
+        default = "default::gc_lifetime",
+        deserialize_with = "deserialize_duration"
+    )]
     pub gc_lifetime: Duration,
     #[serde(default = "default::log_level")]
     pub log_level: LevelFilter,
@@ -153,6 +165,59 @@ where
     Ok(map)
 }
 
+fn parse_duration(s: &str) -> Result<Duration, String> {
+    let mut num = Vec::with_capacity(8);
+    let mut chars = Vec::with_capacity(2);
+    let mut expected_unit = false;
+    for c in s.chars() {
+        if !expected_unit && c.is_numeric() {
+            num.push(c);
+            continue;
+        }
+
+        if !expected_unit && c.is_ascii() {
+            expected_unit = true;
+        }
+        chars.push(c);
+    }
+
+    let n: u64 = num
+        .into_iter()
+        .collect::<String>()
+        .parse()
+        .map_err(|e| format!("invalid value: {}, reason {}", &s, e))?;
+
+    match chars.into_iter().collect::<String>().as_str() {
+        "" => Ok(Duration::from_millis(n)),
+        "s" => Ok(Duration::from_secs(n)),
+        "ms" => Ok(Duration::from_millis(n)),
+        _ => Err(format!("invalid value: {}, expected 10s or 10ms", &s)),
+    }
+}
+
+#[test]
+fn test_parseduration() {
+    // test parse
+    assert_eq!(parse_duration("100s"), Ok(Duration::from_secs(100)));
+    assert_eq!(parse_duration("100ms"), Ok(Duration::from_millis(100)));
+
+    // test default unit
+    assert_eq!(parse_duration("10000"), Ok(Duration::from_millis(10000)));
+
+    // test invalid data
+    assert!(parse_duration("").is_err());
+    assert!(parse_duration("1ms100").is_err());
+    assert!(parse_duration("ms").is_err());
+}
+
+pub fn deserialize_duration<'de, D>(deserializer: D) -> Result<Duration, D::Error>
+where
+    D: Deserializer<'de>,
+{
+    let s: String = String::deserialize(deserializer)?;
+    parse_duration(&s).map_err(DeError::custom)
+}
+
 #[derive(Debug, Error)]
 pub enum ConfigError {
     #[error(transparent)]