The invention provides a design-finalized guardrail capable of being disassembled and provided with spring pins. The design-finalized guardrail comprises stand pillars (1) and cross rods (2) connected between every two stand pillars in the transverse direction; each stand pillar is a rectangular metal pipe with a bottom plate (6) welded at the bottom end; a grooved lap joint(s) (3) with an opening(s) facing upward is/are welded to one or more than one side surface of the upper portion of each stand pillar and a grooved clamping plate(s) (4) with an opening(s) facing inward is/are welded to one or more than one side surface of the lower portion of each stand pillar; a foot blocking board (5) is installed between the corresponding grooved clamping plates of every two adjacent stand pillars in an inserted manner; each cross rod comprises an insertion pipe (2.2) located in the middle section with both ends closed and casing pipes (2.1) arranged at the two ends of the insertion pipe in a sleeving manner, wherein the outer ends of the casing pipes are closed ends and spring pins (5) are located in the casing pipes; the outer ends of the casing pipes at the two sides of each cross rod are located on the corresponding grooved lap joints on every two adjacent stand pillars and bolts are used for connection. The design-finalized guardrail capable of being disassembled and provided with spring pins has the advantages of simple structure, convenient assembly and high construction efficiency; all materials can be recycled and reused many times and construction costs can be reduced greatly.