To　deal　with　large　amount　of　information　and　data　processing　complex　and　finding　no　optimal　solution　in　the　multi-robot　system,　a　modeling　and　solution　method　based　on　combine　auction　of　distributed　task　allocation　problem　was　presented.　The　proposed　method　formally　described　the　multi-robot　system　task　allocation　problem　from　the　view　point　of　seeking　optimal　solution　or　sub-optimal　solution.　Theoretical　analysis　and　numerical　results　show　that　the　method　can　effectively　provide　optimal　solution　or　sub-optimal　solution　for　task　allocation　problem.