Abstract: Nitrogen application at different growth stages of potato will have effect on tuber yield and quality by influencing the vine growth and tuber development. A plot experiment was carried out to study the effects of nitrogen (N) fertilizer application time and application ratio of basal and topdressing on dry matter accumulation and distribution in potato plant, as well as tuber yield. As the experiment material, cultivar‘KX 13’was grown at N application level (180 kg/hm²). The results demonstrated that the treatment with applying 1/2 of all N at the end of tuber formation stage obtained the highest yield (38.1 t/hm²), compared with applying at the early tuber formation stage and the early tuber bulking stage, tuber yield increased by 14.1%(P＜0.05), harvest index increased by 16.7%(P＜0.05). Compared with applying 3/5 of all N at the early tuber formation stage, marketable tuber ratio increased by 4.4%(P＜0.05). The results also demonstrated that dressing N at the early tuber bulking stage or applying 67% of all N at the end of tuber formation stage could decrease the dry matter content of tuber(P＜0.05), but could decrease specific gravity slightly. The suitable N fertilizer application ratio of basal and topdressing could influence the yield and quality of tuber largely.