Abstract: In order to optimize the utilization of sesame leaves, two varieties of sesame leaves at different growth periods were determined and analyzed for their nutrient compositions and in vitro antioxidant activity of polysaccharide extracts. Results showed that with the growth period extending, the content of crude protein in the leaves of both sesame varieties decreased gradually, total sugar and flavonoid contents increased gradually, however, there was no obvious change in the content of total phenol. During the full bloom period, sesame leaves had relatively lower crude fat content and the higher crude fiber content. Sesame leaves throughout the growth period had complete amino acids, which are the good amino acid composition of proteins. In the full bloom stage, the DPPH· scavenging activity and total reducing capacity of polysaccharide extracts were superior to those of the other three growth periods. During the full bloom and mature stages, the total antioxidant capacity and OH· scavenging activity of polysaccharide extracts in sesame leaves were higher than the other two growth periods. In summary, sesame leaves are new resource food with high nutritional value. The polysaccharide extracts from sesame leaves at full bloom and mature stages exhibited better antioxidant activity in vitro.