diff --git a/Documentation/config.txt b/Documentation/config.txt
index 09e95e9e98..f338f0b2c7 100644
--- a/Documentation/config.txt
+++ b/Documentation/config.txt
@@ -921,6 +921,12 @@ relatively high IO latencies.  When enabled, Git will do the
 index comparison to the filesystem data in parallel, allowing
 overlapping IO's.  Defaults to true.
 
+core.unsetenvvars::
+	Windows-only: comma-separated list of environment variables'
+	names that need to be unset before spawning any other process.
+	Defaults to `PERL5LIB` to account for the fact that Git for
+	Windows insists on using its own Perl interpreter.
+
 core.createObject::
 	You can set this to 'link', in which case a hardlink followed by
 	a delete of the source are used to make sure that object creation
diff --git a/compat/mingw.c b/compat/mingw.c
index 272d5e11ea..181e74c23b 100644
--- a/compat/mingw.c
+++ b/compat/mingw.c
@@ -212,6 +212,7 @@ enum hide_dotfiles_type {
 };
 
 static enum hide_dotfiles_type hide_dotfiles = HIDE_DOTFILES_DOTGITONLY;
+static char *unset_environment_variables;
 
 int mingw_core_config(const char *var, const char *value, void *cb)
 {
@@ -223,6 +224,12 @@ int mingw_core_config(const char *var, const char *value, void *cb)
 		return 0;
 	}
 
+	if (!strcmp(var, "core.unsetenvvars")) {
+		free(unset_environment_variables);
+		unset_environment_variables = xstrdup(value);
+		return 0;
+	}
+
 	return 0;
 }
 
@@ -1180,6 +1187,27 @@ static wchar_t *make_environment_block(char **deltaenv)
 	return wenvblk;
 }
 
+static void do_unset_environment_variables(void)
+{
+	static int done;
+	char *p = unset_environment_variables;
+
+	if (done || !p)
+		return;
+	done = 1;
+
+	for (;;) {
+		char *comma = strchr(p, ',');
+
+		if (comma)
+			*comma = '\0';
+		unsetenv(p);
+		if (!comma)
+			break;
+		p = comma + 1;
+	}
+}
+
 struct pinfo_t {
 	struct pinfo_t *next;
 	pid_t pid;
@@ -1198,9 +1226,12 @@ static pid_t mingw_spawnve_fd(const char *cmd, const char **argv, char **deltaen
 	wchar_t wcmd[MAX_PATH], wdir[MAX_PATH], *wargs, *wenvblk = NULL;
 	unsigned flags = CREATE_UNICODE_ENVIRONMENT;
 	BOOL ret;
+	HANDLE cons;
+
+	do_unset_environment_variables();
 
 	/* Determine whether or not we are associated to a console */
-	HANDLE cons = CreateFile("CONOUT$", GENERIC_WRITE,
+	cons = CreateFile("CONOUT$", GENERIC_WRITE,
 			FILE_SHARE_WRITE, NULL, OPEN_EXISTING,
 			FILE_ATTRIBUTE_NORMAL, NULL);
 	if (cons == INVALID_HANDLE_VALUE) {
@@ -2437,6 +2468,8 @@ void mingw_startup(void)
 	/* fix Windows specific environment settings */
 	setup_windows_environment();
 
+	unset_environment_variables = xstrdup("PERL5LIB");
+
 	/* initialize critical section for waitpid pinfo_t list */
 	InitializeCriticalSection(&pinfo_cs);
 
diff --git a/t/t0029-core-unsetenvvars.sh b/t/t0029-core-unsetenvvars.sh
new file mode 100755
index 0000000000..24ce46a6ea
--- /dev/null
+++ b/t/t0029-core-unsetenvvars.sh
@@ -0,0 +1,30 @@
+#!/bin/sh
+
+test_description='test the Windows-only core.unsetenvvars setting'
+
+. ./test-lib.sh
+
+if ! test_have_prereq MINGW
+then
+	skip_all='skipping Windows-specific tests'
+	test_done
+fi
+
+test_expect_success 'setup' '
+	mkdir -p "$TRASH_DIRECTORY/.git/hooks" &&
+	write_script "$TRASH_DIRECTORY/.git/hooks/pre-commit" <<-\EOF
+	echo $HOBBES >&2
+	EOF
+'
+
+test_expect_success 'core.unsetenvvars works' '
+	HOBBES=Calvin &&
+	export HOBBES &&
+	git commit --allow-empty -m with 2>err &&
+	grep Calvin err &&
+	git -c core.unsetenvvars=FINDUS,HOBBES,CALVIN \
+		commit --allow-empty -m without 2>err &&
+	! grep Calvin err
+'
+
+test_done