Nanocarbon has been widely used as a new material in new energy and ecological restoration fields due to its unique physical and chemical properties.In recent years，as its functions are continuously explored，nanocarbon has started to be put into the agricultural field and become a new research hotspot.However，it is still unclear how the addition of nanocarbon affects soil available nutrients and crop yield，and further research is needed.Nanocarbon was used as a fertilizer synergist in different fertilizer formulations to study its effects on soil available nutrients，agronomic traits and yield of rape under field conditions，thus providing a theoretical basis for the efficient use of nanocarbon in agriculture.The field trial was conducted in a greenhouse in Doudian township，Fangshan district，Beijing，with Brassica chinensis L.，variety ‘Guoxia No.1’ as the material crop.Four treatments were set up:chemical fertilizer(CF)，chemical fertilizer+nanocarbon(CF+NC)，organic fertilizer(OM)and organic fertilizer+nanocarbon(OM+NC).Soil available nutrients，rape plant height，leaf area and yield were measured at different growth stages of Brassica chinensis L.The results showed that:(1)Compared with CF and OM，CF+NC and OM+NC treatments increased the soil available nutrient content and increased the soil available potassium content by 37.3% and 27.4%，soil ammonium nitrogen content by 35.5% and 35.0%，and soil nitrate nitrogen content by 52.0% and 49.9%，respectively，in vigorous growth period of Brassica chinensis L.(2)The addition of nanocarbon promoted the growth of Brassica chinensis L.；Compared with CF and OM，CF+NC and OM+NC treatments increased the height of Brassica chinensis L.plants by 9.7% and 5.6%，leaf area by 13.9% and 12.9%，dry weight by 15.6% and 14.7%，and yield by 19.8% and 18.0% at harvest stage，respectively.Compared to fertilizer application alone，the application of nanocarbon with inorganic and organic fertilizers significantly increased the contents of soil available nutrients，promoted the growth and development of Brassica chinensis L.and improved the yield.