In order to evaluate the yielding ability and stability, and adaptability of different maize varieties, as well as the discrimination and representativeness of test sites in maize regional trial, the GGEBiplotGUI package of free and open source R language was used to analyze 18 varieties(including Zhengdan 958 as the control ) and 10 test sites in Huaibei, Jiangsu Province in 2018. The results showed that the 10 test sites were divided into three small "ecological zones", among which Fengxian, Tongshan, Pizhou and Shuyang were the first group, Huai'an, Suining and Suqian were the second group, Binhai, Gangbu farm of Lianyungang and Jingsetianhua of Huai'an were the third group. Ruiyou 288, HT736, X1601 and Ly1666 had high yields, among which the yield of Ruiyou 288 was high and stable, and the yields of the other three weren’t stable. The three test sites, Huai'an, Suining and Shuyang had good discrimination and representativeness. The test sites, Gangbu farm of Lianyungang and Jingsetianhua of Huai'an had strong discrimination but poor representativeness. The test site of Suqian had strong representativeness but poor discrimination.