The spatters created during laser welding are considered as essential information for welding quality inspection. This paper proposes a laser welding quality inspection method based on the high-speed visual detection. A high-power disk laser bead-on-plate welding of Type 304 austenitic stainless workpiece was experimented and two high-speed cameras were used to capture the spatter images. Spatter feature parameters were extracted by image processing, and the spatter volume was used to evaluate the welding quality. By comparing the spatter information with molten pool width, this paper investigates the internal relation between the welding quality and the spatter feature parameters. Experimental results proved that the proposed spatter feature extraction method help to guarantee an accurate evaluation on the quality of high-power disk laser welding.