diff --git a/ILRepack/Application.cs b/ILRepack/Application.cs
index 856c5546..0274b3e8 100644
--- a/ILRepack/Application.cs
+++ b/ILRepack/Application.cs
@@ -154,6 +154,7 @@ allows dropping members denoted by this attribute name when merging
  - /keepotherversionreferences
                       take reference assembly version into account when removing references
 
+ - /preservetimestamp preserve original file PE timestamp
  - /skipconfig        skips merging config files
  - /illink            merge IL Linker files
  - /xmldocs           merges XML documentation as well
diff --git a/ILRepack/ILRepack.cs b/ILRepack/ILRepack.cs
index 088415c8..12ad4283 100644
--- a/ILRepack/ILRepack.cs
+++ b/ILRepack/ILRepack.cs
@@ -446,10 +446,14 @@ private void RepackCore(string tempOutputDirectory)
                     StrongNameKeyBlob = signingStep.KeyInfo?.KeyBlob,
                     WriteSymbols = Options.DebugInfo && symbolWriterProvider != null,
                     SymbolWriterProvider = symbolWriterProvider,
-                    DeterministicMvid = true,
-                    Timestamp = ComputeDeterministicTimestamp()
+                    DeterministicMvid = true
                 };
 
+                if (!Options.PreserveTimestamp)
+                {
+                    parameters.Timestamp = ComputeDeterministicTimestamp();
+                }
+
                 Logger.Verbose($"Writing temporary assembly: {tempOutputFilePath}");
                 TargetAssemblyDefinition.Write(tempOutputFilePath, parameters);
 
diff --git a/ILRepack/RepackOptions.cs b/ILRepack/RepackOptions.cs
index 4f3f9b8f..e5eeb388 100644
--- a/ILRepack/RepackOptions.cs
+++ b/ILRepack/RepackOptions.cs
@@ -75,6 +75,7 @@ public string ExcludeFile
         public IEnumerable<string> SearchDirectories { get; set; } = Array.Empty<string>();
         public bool UnionMerge { get; set; }
         public Version Version { get; set; }
+        public bool PreserveTimestamp { get; set; }
         public bool SkipConfigMerge { get; set; }
         public bool MergeIlLinkerFiles { get; set; }
         public bool XmlDocumentation { get; set; }
@@ -260,6 +261,7 @@ void Parse()
             var version = cmd.Option("ver");
             if (!string.IsNullOrEmpty(version))
                 Version = new Version(version);
+            PreserveTimestamp = cmd.Modifier("preservetimestamp");
             SkipConfigMerge = cmd.Modifier("skipconfig");
             MergeIlLinkerFiles = cmd.Modifier("illink");
             XmlDocumentation = cmd.Modifier("xmldocs");