diff --git a/src/cmd/go/alldocs.go b/src/cmd/go/alldocs.go
index 6800e1c7d2..586bc1a7ca 100644
--- a/src/cmd/go/alldocs.go
+++ b/src/cmd/go/alldocs.go
@@ -542,6 +542,9 @@
 //		The line number of the directive in the source file.
 //	$GOPACKAGE
 //		The name of the package of the file containing the directive.
+//	$GOROOT
+//		The GOROOT directory for the 'go' command that invoked the
+//		generator, containing the Go toolchain and standard library.
 //	$DOLLAR
 //		A dollar sign.
 //
diff --git a/src/cmd/go/internal/generate/generate.go b/src/cmd/go/internal/generate/generate.go
index 0021bcc75a..a46f4f8908 100644
--- a/src/cmd/go/internal/generate/generate.go
+++ b/src/cmd/go/internal/generate/generate.go
@@ -84,6 +84,9 @@ Go generate sets several variables when it runs the generator:
 		The line number of the directive in the source file.
 	$GOPACKAGE
 		The name of the package of the file containing the directive.
+	$GOROOT
+		The GOROOT directory for the 'go' command that invoked the
+		generator, containing the Go toolchain and standard library.
 	$DOLLAR
 		A dollar sign.
 
@@ -326,6 +329,7 @@ func isGoGenerate(buf []byte) bool {
 // single go:generate command.
 func (g *Generator) setEnv() {
 	g.env = []string{
+		"GOROOT=" + cfg.GOROOT,
 		"GOARCH=" + cfg.BuildContext.GOARCH,
 		"GOOS=" + cfg.BuildContext.GOOS,
 		"GOFILE=" + g.file,
diff --git a/src/cmd/go/testdata/script/build_trimpath_goroot.txt b/src/cmd/go/testdata/script/build_trimpath_goroot.txt
index 91e5107e58..a26cfd23be 100644
--- a/src/cmd/go/testdata/script/build_trimpath_goroot.txt
+++ b/src/cmd/go/testdata/script/build_trimpath_goroot.txt
@@ -62,6 +62,11 @@ stderr 'cannot find package "runtime" in any of:\n\t\(\$GOROOT not set\)\n\t'$WO
 stdout '^GOROOT $'
 stdout 'cannot find package "runtime" in any of:\n\t\(\$GOROOT not set\)\n\t'$WORK${/}gopath${/}src${/}runtime' \(from \$GOPATH\)$'
 
+env GOFLAGS=-trimpath
+go generate .
+stdout '^GOROOT '$TESTGO_GOROOT'$'
+stdout '^runtime '$TESTGO_GOROOT${/}src${/}runtime'$'
+
 -- go.mod --
 module example
 
@@ -69,6 +74,8 @@ go 1.19
 -- main.go --
 package main
 
+//go:generate go run .
+
 import (
 	"fmt"
 	"go/build"