It is meaningful to clarify the effects of tea planting on total nitrogen and mineral nitrogen in soil aggregates for providing a theoretical basis of applying nitrogen fertilizer. The effects of different tea cultivars (Fuding Dabaicha, Chuancha No. 3, Chuannong Huangyazao and Chuanmu No. 217) on total nitrogen and mineral nitrogen content in soil aggregates were studied by field investigation and indoor analysis. The results showed that: (1) As the decrease of particle size, the content of aggregates in each tea planting soil decreased firstly and then increased. The content of >2 mm aggregate was significantly higher than that of other aggregates, accounting for about 38.32%~66.26% of the total content. (2) With the decrease of aggregate particle size, the total nitrogen content of the soil of each tea cultivar decreased firstly and then stabilized, while the contents of ammonium nitrogen and nitrate nitrogen showed the opposite trend. (3) The contents of each nitrogen component in the soil of planting Fuding Dabaicha were higher than those of other cultivars. The trend of mineral nitrogen content in different soil layers was similar. (4) The reserves of each nitrogen component were the highest in > 2 mm aggregates, which were 6.25~11.44 kg/hm², 13.09~42.66, 14.38~51.03 g/hm², respectively. (5) The reserves of total nitrogen, ammonium nitrogen and nitrate nitrogen of the soil planted with Chuannong Huangyazao were higher than other cultivars. These research results provide a theoretical basis for the rational application of nitrogen fertilizer in tea-planting soils in the hilly areas of western Sichuan.