diff --git a/src/MSDIAL5/MsdialCore/Parameter/ParameterBase.cs b/src/MSDIAL5/MsdialCore/Parameter/ParameterBase.cs
index b0b1c0f39..7f40291f2 100644
--- a/src/MSDIAL5/MsdialCore/Parameter/ParameterBase.cs
+++ b/src/MSDIAL5/MsdialCore/Parameter/ParameterBase.cs
@@ -1148,7 +1148,7 @@ public class AlignmentBaseParameter {
         [Key(3)]
         public float SpectrumSimilarityAlignmentFactor { get; set; } = 0.5F;
         [Key(4)]
-        public float Ms1AlignmentTolerance { get; set; } = 0.5F;
+        public float Ms1AlignmentTolerance { get; set; } = 0.015F;
         [Key(5)]
         public float RetentionTimeAlignmentTolerance { get; set; } = 0.10F;
         [Key(6)]
diff --git a/src/MSDIAL5/MsdialGcMsApi/Algorithm/Alignment/GcmsPeakJoiner.cs b/src/MSDIAL5/MsdialGcMsApi/Algorithm/Alignment/GcmsPeakJoiner.cs
index 1e42d82d4..f52f84e61 100644
--- a/src/MSDIAL5/MsdialGcMsApi/Algorithm/Alignment/GcmsPeakJoiner.cs
+++ b/src/MSDIAL5/MsdialGcMsApi/Algorithm/Alignment/GcmsPeakJoiner.cs
@@ -45,7 +45,7 @@ protected GcmsPeakJoiner(AlignmentIndexType indextype, RiCompoundType riCompound
         _comparer = comparer;
         _alignmentParameter = parameter.AlignmentBaseParam;
         _riCompoundType = riCompoundType;
-        _msMatchParam = new MsRefSearchParameterBase() { Ms1Tolerance = 0.5F, Ms2Tolerance = 0.5F, MassRangeBegin = 0, MassRangeEnd = 2000 };
+        _msMatchParam = new MsRefSearchParameterBase { Ms1Tolerance = .5f, Ms2Tolerance = .5f, MassRangeBegin = 0, MassRangeEnd = 2000, };
         _parameter = parameter;
         _evaluator = evaluator;
         _refer = refer;
diff --git a/src/MSDIAL5/MsdialGcMsApi/Parameter/MsdialGcmsParameter.cs b/src/MSDIAL5/MsdialGcMsApi/Parameter/MsdialGcmsParameter.cs
index 61dad1435..fcfc130f2 100644
--- a/src/MSDIAL5/MsdialGcMsApi/Parameter/MsdialGcmsParameter.cs
+++ b/src/MSDIAL5/MsdialGcMsApi/Parameter/MsdialGcmsParameter.cs
@@ -10,7 +10,10 @@ namespace CompMs.MsdialGcMsApi.Parameter {
     [MessagePackObject]
     public class MsdialGcmsParameter : ParameterBase {
 
-        public MsdialGcmsParameter(bool isLabUseOnly) : base(isLabUseOnly) { this.MachineCategory = MachineCategory.GCMS; }
+        public MsdialGcmsParameter(bool isLabUseOnly) : base(isLabUseOnly) {
+            this.MachineCategory = MachineCategory.GCMS;
+            AlignmentBaseParam.Ms1AlignmentTolerance = .5f;
+        } 
 
         [SerializationConstructor]
         public MsdialGcmsParameter() : this(isLabUseOnly: false) { }