Based on the sub module control system design,a sawn timber sorting device was designed and developed.A single chip microcomputer,which controls transportation,separation and detection of sawn timber was used as the main control unit with multi sensors and contact switches as feedback information input.The test results showed that the prototype is reliable in separating sawn timber and detecting uneven colored and off-sized timber,which is helpful of improving automation and production efficiency of sawn timber sorting and detection.