Abstract: In order to promote the popularization and application of a new rice variety Longdao 210,the breeding method, breeding process, yield performance, characteristics and supporting cultivation techniques of Longdao 210 were briefly introduced in this paper.Longdao 210 was a nwe variety bred by pedigree method with Dongnong 423 as female parent and Longdao 21 as male parent.It was suitable for planting in the first accumulation zone of Heilongjiang Province by genealogy method.In 2020,Longdao 210 obtained the protection right of new plant varieties, announcement number CNA034129 E.On June 11,2021,Longdao 210 was approved by Heilongjiang Provincial Crop Varieties Examination Committee with the number of Heisheng Rice 20210009.In the regional experiment, the average yield of Longdao 210 was 8 046.0 kg·ha^-1,which increased by 7.4% compared with the control variety Longdao 18.The average yield of Longdao 210 in production test was 8 328.1 kg·ha^-1,7.5% higher than that of the control variety Longdao 18.This variety is suitable for planting in the area of active accumulated temperature ≥10 ℃ and 2 700 ℃ in Heilongjiang Province.