Studied the change of Lycium barbarum polysaccharides (LBP) in different growth periods, by using the wolfberries in different growth periods as research objects, and analyzed the LBP composition by HPLC. Taking VC as the control sample, the LBP’s activities of scavenging hydroxyl radicals, superoxide anions, DPPH and ABTS were analyzed and compared in different growth periods. The rheological characteristics of LBP in different growth periods were analyzed by a rheometer. The results indicated that the monosaccharide composition of LBP was the same in different growth periods, but the monosaccharide molar ratios of the polysaccharides were significantly different. The antioxidant activity in vitro of the polysaccharides of the first-crop fruits was the strongest. The polysaccharides viscosities of green wolfberries, coloring wolfberries, first-crop wolfberries, summer wolfberries and autumn wolfberries were 1.02, 1.26, 1.53, 1.49 and 1.37 Pas, respectively. This study provided the theoretical basis for the future study on the accumulation and change of LBP and the formation principle of LBP in different growth periods.