diff --git a/src/main/java/net/fabricmc/loom/build/nesting/JarNester.java b/src/main/java/net/fabricmc/loom/build/nesting/JarNester.java
index 028f9b2fb..a90d5de01 100644
--- a/src/main/java/net/fabricmc/loom/build/nesting/JarNester.java
+++ b/src/main/java/net/fabricmc/loom/build/nesting/JarNester.java
@@ -53,7 +53,7 @@ public static void nestJars(Collection<File> jars, List<NestedFile> forgeJars, F
 			return;
 		}
 
-		Preconditions.checkArgument(FabricModJsonFactory.isModJar(modJar, platform), "Cannot nest jars into none mod jar " + modJar.getName());
+		Preconditions.checkArgument(FabricModJsonFactory.isNestableModJar(modJar, platform), "Cannot nest jars into none mod jar " + modJar.getName());
 
 		try {
 			ZipUtils.add(modJar.toPath(), jars.stream().map(file -> {
@@ -78,7 +78,7 @@ public static void nestJars(Collection<File> jars, List<NestedFile> forgeJars, F
 
 				for (File file : jars) {
 					String nestedJarPath = "META-INF/jars/" + file.getName();
-					Preconditions.checkArgument(FabricModJsonFactory.isModJar(file, platform), "Cannot nest none mod jar: " + file.getName());
+					Preconditions.checkArgument(FabricModJsonFactory.isNestableModJar(file, platform), "Cannot nest none mod jar: " + file.getName());
 
 					for (JsonElement nestedJar : nestedJars) {
 						JsonObject jsonObject = nestedJar.getAsJsonObject();
@@ -115,7 +115,7 @@ public static void nestJars(Collection<File> jars, List<NestedFile> forgeJars, F
 
 				for (File file : jars) {
 					String nestedJarPath = "META-INF/jars/" + file.getName();
-					Preconditions.checkArgument(FabricModJsonFactory.isModJar(file, platform), "Cannot nest none mod jar: " + file.getName());
+					Preconditions.checkArgument(FabricModJsonFactory.isNestableModJar(file, platform), "Cannot nest none mod jar: " + file.getName());
 
 					for (JsonElement nestedJar : nestedJars) {
 						String nestedJarString = nestedJar.getAsString();
diff --git a/src/main/java/net/fabricmc/loom/util/fmj/FabricModJsonFactory.java b/src/main/java/net/fabricmc/loom/util/fmj/FabricModJsonFactory.java
index 21653eeee..d5b806def 100644
--- a/src/main/java/net/fabricmc/loom/util/fmj/FabricModJsonFactory.java
+++ b/src/main/java/net/fabricmc/loom/util/fmj/FabricModJsonFactory.java
@@ -175,6 +175,16 @@ public static boolean isModJar(Path input, ModPlatform platform) {
 		return ZipUtils.contains(input, FABRIC_MOD_JSON);
 	}
 
+	public static boolean isNestableModJar(File file, ModPlatform platform) {
+		return isNestableModJar(file.toPath(), platform);
+	}
+
+	public static boolean isNestableModJar(Path input, ModPlatform platform) {
+		// Forge don't care if the main jar is mod jar.
+		if (platform == ModPlatform.FORGE) return true;
+		return isModJar(input, platform);
+	}
+
 	public static boolean containsMod(FileSystemUtil.Delegate fs, ModPlatform platform) {
 		if (Files.exists(fs.getPath("architectury.common.marker"))) {
 			return true;