diff --git a/pkg/sessionctx/vardef/tidb_vars.go b/pkg/sessionctx/vardef/tidb_vars.go
index 942aeee716..966bc1a545 100644
--- a/pkg/sessionctx/vardef/tidb_vars.go
+++ b/pkg/sessionctx/vardef/tidb_vars.go
@@ -1658,7 +1658,7 @@ const (
 	DefOptEnableProjectionPushDown                    = true
 	DefTiDBEnableSharedLockPromotion                  = false
 	DefTiDBTSOClientRPCMode                           = TSOClientRPCModeDefault
-	DefTiDBCircuitBreakerPDMetaErrorRatePct           = 0
+	DefTiDBCircuitBreakerPDMetaErrorRatePct           = 0.0
 	DefTiDBAccelerateUserCreationUpdate               = false
 	DefTiDBEnableTSValidation                         = true
 )
@@ -1788,6 +1788,8 @@ var (
 	SchemaCacheSize              = atomic.NewUint64(DefTiDBSchemaCacheSize)
 	SchemaCacheSizeOriginText    = atomic.NewString(strconv.Itoa(DefTiDBSchemaCacheSize))
 	AccelerateUserCreationUpdate = atomic.NewBool(DefTiDBAccelerateUserCreationUpdate)
+
+	CircuitBreakerPDMetadataErrorRateThresholdPct = atomic.NewFloat64(0.0)
 )
 
 func serverMemoryLimitDefaultValue() string {
diff --git a/pkg/sessionctx/variable/sysvar.go b/pkg/sessionctx/variable/sysvar.go
index 4ccb275e93..96ef7ea530 100644
--- a/pkg/sessionctx/variable/sysvar.go
+++ b/pkg/sessionctx/variable/sysvar.go
@@ -3563,14 +3563,24 @@ var defaultSysVars = []*SysVar{
 			return (*SetPDClientDynamicOption.Load())(vardef.TiDBTSOClientRPCMode, val)
 		},
 	},
-	{Scope: vardef.ScopeGlobal, Name: vardef.TiDBCircuitBreakerPDMetadataErrorRateThresholdPct, Value: strconv.Itoa(vardef.DefTiDBCircuitBreakerPDMetaErrorRatePct), Type: vardef.TypeUnsigned, MinValue: 0, MaxValue: 100,
+	{Scope: vardef.ScopeGlobal, Name: vardef.TiDBCircuitBreakerPDMetadataErrorRateThresholdPct, Value: strconv.FormatFloat(vardef.DefTiDBCircuitBreakerPDMetaErrorRatePct, 'f', -1, 64),
+		Type: vardef.TypeFloat, MinValue: 0, MaxValue: 1,
+		GetGlobal: func(_ context.Context, s *SessionVars) (string, error) {
+			return strconv.FormatFloat(vardef.CircuitBreakerPDMetadataErrorRateThresholdPct.Load(), 'f', -1, 64), nil
+		},
 		SetGlobal: func(_ context.Context, s *SessionVars, val string) error {
+			v := tidbOptFloat64(val, vardef.DefTiDBCircuitBreakerPDMetaErrorRatePct)
+			if v < 0 || v > 1 {
+				return errors.Errorf("invalid tidb_cb_pd_metadata_error_rate_threshold_pct value %s", val)
+			}
+			vardef.CircuitBreakerPDMetadataErrorRateThresholdPct.Store(v)
 			if ChangePDMetadataCircuitBreakerErrorRateThresholdPct != nil {
-				ChangePDMetadataCircuitBreakerErrorRateThresholdPct(uint32(tidbOptPositiveInt32(val, vardef.DefTiDBCircuitBreakerPDMetaErrorRatePct)))
+				ChangePDMetadataCircuitBreakerErrorRateThresholdPct(uint32(v * 100))
 			}
 			return nil
 		},
 	},
+
 	{Scope: vardef.ScopeGlobal, Name: vardef.TiDBAccelerateUserCreationUpdate, Value: BoolToOnOff(vardef.DefTiDBAccelerateUserCreationUpdate), Type: vardef.TypeBool,
 		SetGlobal: func(_ context.Context, s *SessionVars, val string) error {
 			vardef.AccelerateUserCreationUpdate.Store(TiDBOptOn(val))
diff --git a/pkg/sessionctx/variable/sysvar_test.go b/pkg/sessionctx/variable/sysvar_test.go
index 6391132ffb..e5527d6c6c 100644
--- a/pkg/sessionctx/variable/sysvar_test.go
+++ b/pkg/sessionctx/variable/sysvar_test.go
@@ -1773,16 +1773,20 @@ func TestTiDBCircuitBreakerPDMetadataErrorRateThresholdPct(t *testing.T) {
 	require.Equal(t, "[variable:1292]Truncated incorrect tidb_cb_pd_metadata_error_rate_threshold_pct value: '-1'", warn.Error())
 
 	// Too high, will get lowered to the max value
-	val, err = sv.Validate(vars, "101", vardef.ScopeGlobal)
+	val, err = sv.Validate(vars, "1.1", vardef.ScopeGlobal)
 	require.NoError(t, err)
 	require.Equal(t, strconv.FormatUint(GetSysVar(vardef.TiDBCircuitBreakerPDMetadataErrorRateThresholdPct).MaxValue, 10), val)
 	warn = vars.StmtCtx.GetWarnings()[1].Err
-	require.Equal(t, "[variable:1292]Truncated incorrect tidb_cb_pd_metadata_error_rate_threshold_pct value: '101'", warn.Error())
+	require.Equal(t, "[variable:1292]Truncated incorrect tidb_cb_pd_metadata_error_rate_threshold_pct value: '1.1'", warn.Error())
 
 	// valid
-	val, err = sv.Validate(vars, "10", vardef.ScopeGlobal)
+	val, err = sv.Validate(vars, "0.9", vardef.ScopeGlobal)
 	require.NoError(t, err)
-	require.Equal(t, "10", val)
+	require.Equal(t, "0.9", val)
+
+	val, err = sv.Validate(vars, "0.0", vardef.ScopeGlobal)
+	require.NoError(t, err)
+	require.Equal(t, "0.0", val)
 }
 
 func TestEnableWindowFunction(t *testing.T) {