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Cultivar selection is important for alfalfa (Medicago sativa L.) hay production. From 2009 to 2012, a ifeld study was conducted to evaluate the dry matter yield (DMY) of 28 cultivars in Cangzhou District of Hebei province, China, and to determine the most suitable cultivars for this province and other zones with similar climate conditions. 28 alfalfa cultivars were sown in late March of 2009 and were harvested for hay four times in each subsequent year. The results showed that the climatic conditions resulted in signiifcant differences in annual DMY among years, with the second year being the highest and the ifrst year the lowest. The top ifve cultivars with the highest total DMY were L2750 (62.75 t ha-1), Horn (62.72 t ha-1), 86-266 (61.55 t ha-1), German (61.44 t ha-1) and Zhongmu 1 (61.18 t ha-1), respectively. Across all four years, ifrst harvest had the highest ratios to annual DMY except the cultivar of Rambler, while the fourth harvest had the lowest ratio. There were positive correlation relationships between DMY of each harvest and annual DMY, and the correlation coefifcients were all signiifcant in four years. And the path coefifcients of ifrst harvest were always the highest in four years. The qualities showed small variations among these cultivars and the cultivar L3750 presented the highest crude protein in both years. Crude protein had signiifcant positive correlation with relative feed value (RFV) in both years while crude ifber had signiifcant negative correlation with RFV and crude ifber.