Abstract: In order to explore the efficacy and safety of 20% pendimethalin·pyrazosulfuron-ethyl WP on Echinochloa crusgalli, Monochoria korsakowii（L.） Beauv, Alisma orientale（Sam.） Juzep, and Carex phacota in the rice field, the experiment was designed as follows: 20% pendimethalin·pyrazosulfuron-ethyl WP of 165,195,225 and 390 g·ha^-1, 330 g·L ^-1 pendimethalin EC of 990 g·ha^-1, and 10% pyrazosulfuron-ethyl WP of 22.5 g·ha^-1 were sprayed on the rice stems and leaves 35 d after transplantation. Water spraying and manual weeding were set as control. Safety evaluations were committed by visual observation 3 days and 7 days after herbicide spraying. Each individual-plant control efficiency of the five kinds of weed above and the total plant control efficiency were studied 15 days after herbicide spraying. Each individual-plant control efficiency, each fresh-weight control efficiency, the total plant control efficiency and the total fresh-weight control efficiency were researched 30 days after herbicide spraying. The highest total plant control efficiency existed in treatment 4(20% pendimethalin·pyrazosulfuron-ethyl WP of 390 g·ha^-1), 80.83%, followed by treatment 3(20% pendimethalin·pyrazosulfuron-ethyl WP of 225 g·ha^-1), 78.19%, except for manual weeding 15 days after herbicide spraying. 30 days after herbicide spraying, the highest total plant control efficiency and total plant control efficiency emerged from treatment 4, 96.72% and 95.66%, followed by treatment 3, 95.31% and 94.18%. Treatment 4 made the highest yield increase of 21.54%, followed by treatment 3, 20.31%. 35 days after transplantation, spraying 20% pendimethalin·pyrazosulfuron-ethyl WP on the stems and leaves is capable of preventing and controlling the occurrence of the 5 kinds of weeds above in the rice transplantation field with a positive safety evaluation. The yield would increase by over 20%.