diff --git a/oap-server/server-alarm-plugin/src/main/java/org/apache/skywalking/oap/server/core/alarm/provider/RulesReader.java b/oap-server/server-alarm-plugin/src/main/java/org/apache/skywalking/oap/server/core/alarm/provider/RulesReader.java
index 9f5f9478c..e0909dea7 100644
--- a/oap-server/server-alarm-plugin/src/main/java/org/apache/skywalking/oap/server/core/alarm/provider/RulesReader.java
+++ b/oap-server/server-alarm-plugin/src/main/java/org/apache/skywalking/oap/server/core/alarm/provider/RulesReader.java
@@ -76,7 +76,8 @@ public class RulesReader {
                         alarmRule.setOp((String) settings.get("op"));
                         alarmRule.setPeriod((Integer) settings.getOrDefault("period", 1));
                         alarmRule.setCount((Integer) settings.getOrDefault("count", 1));
-                        alarmRule.setSilencePeriod((Integer) settings.getOrDefault("silence-period", -1));
+                        // How many times of checks, the alarm keeps silence after alarm triggered, default as same as period.
+                        alarmRule.setSilencePeriod((Integer) settings.getOrDefault("silence-period", alarmRule.getPeriod()));
                         alarmRule.setMessage(
                             (String) settings.getOrDefault("message", "Alarm caused by Rule " + alarmRule
                                 .getAlarmRuleName()));