diff --git a/base/random.jl b/base/random.jl
index 074cd1cbc7bc3..01912627a784c 100644
--- a/base/random.jl
+++ b/base/random.jl
@@ -220,7 +220,7 @@ end
 ## srand()
 
 """
-    srand([rng=GLOBAL_RNG], [seed])
+    srand([rng=GLOBAL_RNG], [seed]) -> rng
 
 Reseed the random number generator. If a `seed` is provided, the RNG will give a
 reproducible sequence of numbers, otherwise Julia will get entropy from the system. For
diff --git a/test/random.jl b/test/random.jl
index 90a126a05d996..daa698baea0d5 100644
--- a/test/random.jl
+++ b/test/random.jl
@@ -479,3 +479,18 @@ let seed = rand(UInt32, 10)
     resize!(seed, 4)
     @test r.seed != seed
 end
+
+# srand(rng, ...) returns rng (#21248)
+let g = Base.Random.GLOBAL_RNG,
+    m = MersenneTwister(0)
+    @test srand() === g
+    @test srand(rand(UInt)) === g
+    @test srand(rand(UInt32, rand(1:10))) === g
+    @test srand(@__FILE__) === g
+    @test srand(@__FILE__, rand(1:10)) === g
+    @test srand(m) === m
+    @test srand(m, rand(UInt)) === m
+    @test srand(m, rand(UInt32, rand(1:10))) === m
+    @test srand(m, rand(1:10)) === m
+    @test srand(m, @__FILE__, rand(1:10)) === m
+end