Abstract: The SKT jigging machine is one of the extensively used coal cleaning machines in China. An introduction is made in the paper to the work made in recent years on the improvement and perfection of the air valve,structural design,reject extractor and control system of the SKT jigging machine,as well as the extended application of the machine in underground deshaling and lumpy coal pre-deshaling,wide size range power coal separation,anthracite high-density separation and urban garbage sorting operations.