Field experiment was carried out to investigate the effect of soil matric potential (SMP) on tomato yield, evapotranspiration (ET), water use efficiency (WUE) and irrigation water use efficiency (IWUE) under drip irrigation condition in North China Plain. The experiment included five treatments, which controlled SMP at 0.2m depth immediately under drip emitter higher than −10 (S1), −20 (S2), −30 (S3), −40 (S4) and −50kPa (S5), respectively, after tomato plant establishment. The results showed that different SMP affected irrigation amount and tomato ET. Irrigation amount decreased from 185mm (S1) to 83.6mm (S5) in 2004, and from 165mm (S1) to 109mm (S5) in 2005, respectively. The ET decreased from 270mm (S1) to 202mm (S5) in both years. However, it was found that SMP did not affect the tomato yield significantly, for the range of SMP investigated. Both WUE and IWUE increased as SMP decreased. The maximum WUE (253 and 217kg/hamm) and IWUE (620 and 406kg/hamm) were for S5 in 2 years, whereas the minimum WUE (178 and 155kg/hamm) and IWUE 261 and 259kg/hamm) were for S1 in 2004 and 2005. Based on the above results, therefore, it is recommended that if the tomatoes are well irrigated (SMP is higher than −20kPa) during establishment, controlling SMP higher than −50kPa at 0.2m depth immediately under drip emitter can be used as an indicator for drip irrigation scheduling during following period of tomato growth in North China Plain.