【Abstract】 Objective To study the synthesis control effects of the poison bait and the gel bait to Blattella germanica in the passenger trains.  Methods One percent acephate and 1% Yekang gel bait were applied exclusively or both were jointly used in the passenger trains. The density of B.germanica was monitored before and after treatment respectively. Results There was significant difference between the combined application of poison bait and gel bait and single application of poison bait（χ2＝17.146，P＝0.000）. The combined application of poison bait and gel bait also significantly differed compared to that of the single gel bait（χ2＝15.499，P＝0.000）. Conclusion The combined application of cockroach poison bait and gel bait had a remarkable efficacy to the fast killing of B.germanica and the maintenance of low cockroach density in the passenger trains.