【Abstract】 Objective To learn the infestation situation of indoor cockroach in Chongqing, and control effectively its density to accumulate experience for its large scale control. Methods The residual spraying and toxic baits were used to kill cockroach, and the  control efficacy was evaluated by chemicals simulating method and visual method. Results The infestation rate reached 27.75% before treatment, and there was significant difference among the infestation situation of cockroach at six different places（χ2＝91.272, P＜0.01）.After treatment, it decreased to 6.46% and the killing rate was 76.72%. The control efficacy in the school was the best, and the killing rate reached 91.95%. The second was in the farm product trade market with the value of 86.19%. It was the worst in five small shops, and its killing rate to cockroach was only 60.79%. There was also significant difference among the control efficacy at six places（χ2＝55.235, P＜0.01）. Conclusion The control efficacy to cockroach was very distinct, which effectively reduced the density of cockroach. The results also showed many factors such as environment, work force and concern degree would affect the control effect. The environmental condition was better, the control of cockroaches was easier. The work force was bigger and the degree of concern was higher, the killing effect was more remarkable.