diff --git a/src/math/floor_asm.go b/src/math/floor_asm.go
index 5cb45f5a7e84e1..1b06b8def9c650 100644
--- a/src/math/floor_asm.go
+++ b/src/math/floor_asm.go
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-//go:build 386 || amd64 || arm64 || ppc64 || ppc64le || riscv64 || s390x || wasm
+//go:build 386 || amd64 || arm64 || loong64 || ppc64 || ppc64le || riscv64 || s390x || wasm
 
 package math
 
diff --git a/src/math/floor_loong64.s b/src/math/floor_loong64.s
new file mode 100644
index 00000000000000..0df7deee60588d
--- /dev/null
+++ b/src/math/floor_loong64.s
@@ -0,0 +1,41 @@
+// Copyright 2024 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+//
+// derived from math/floor_riscv64.s
+
+#include "textflag.h"
+
+#define ROUNDFN(NAME, FUNC)	\
+TEXT NAME(SB),NOSPLIT,$0;	\
+	MOVD	x+0(FP), F0;	\
+	MOVV	F0, R11;	\
+	/* 1023: bias of exponent, [-2^53, 2^53]: exactly integer represent range */;	\
+	MOVV	$1023+53, R12;	\
+	/* Drop all fraction bits */;	\
+	SRLV	$52, R11, R11;	\
+	/* Remove sign bit */;	\
+	AND	$0x7FF, R11, R11;	\
+	BLTU	R12, R11, isExtremum;	\
+normal:;	\
+	FUNC	F0, F2;	\
+	MOVV	F2, R10;	\
+	BEQ	R10, R0, is0;	\
+	FFINTDV	F2, F0;	\
+/* Return either input is +-Inf, NaN(0x7FF) or out of precision limitation */;	\
+isExtremum:;	\
+	MOVD	F0, ret+8(FP);	\
+	RET;	\
+is0:;	\
+	FCOPYSGD	F0, F2, F2;	\
+	MOVD	F2, ret+8(FP);	\
+	RET
+
+// func archFloor(x float64) float64
+ROUNDFN(·archFloor, FTINTRMVD)
+
+// func archCeil(x float64) float64
+ROUNDFN(·archCeil, FTINTRPVD)
+
+// func archTrunc(x float64) float64
+ROUNDFN(·archTrunc, FTINTRZVD)
diff --git a/src/math/floor_noasm.go b/src/math/floor_noasm.go
index 6754ca8fc806e1..34bd292f0e7751 100644
--- a/src/math/floor_noasm.go
+++ b/src/math/floor_noasm.go
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-//go:build !386 && !amd64 && !arm64 && !ppc64 && !ppc64le && !riscv64 && !s390x && !wasm
+//go:build !386 && !amd64 && !arm64 && !loong64 && !ppc64 && !ppc64le && !riscv64 && !s390x && !wasm
 
 package math