Abstract: The effects of irrigation frequency and soil matric potential on potato growth and water use efficiency(WUE) under drip irrigation in North China were studied. Results suggested that drip irrigation frequency and soil matric potential significantly influence the distribution of soil water (soil matric potential). The lower the irrigation frequency was, the larger the dry zone in the topsoil before irrigation and the larger the wetting range after irrigation were. Targeted soil matric potential at 20 cm immediately under drip emitter clearly influences soil matric potentials in soil depth from 0 to 50 cm. The higher the targeted soil matric potential was, the higher the average soil matric potential in soil depth from 0 to 50 cm was. The lower the targeted potential was, the larger the dry zone around drip emitter was. During the middle potato growing period when soil matric potential went lower than -45 kPa, potato tuber bulking rate decreased immediately. Total tuber yield and WUE were in an prior order of(-25 kPa)>(-35 kPa)>(-15 kPa)>(-45 kPa)>(-55 kPa). Total yield and WUE under different irrigation frequency treatments were in an prior order of (once every day)>(once every two days)>(once every three days)>(once every four days)>(once every six days)>(once every eight days). The experimental results showed that for favorable potato growth under drip irrigation in North China, soil matric potential should be maintained around -25 kPa and drip irrigation frequency should be once every day.