Abstract: The aim of this research was to optimize the method for making Amaranthus hypochondriacus silage. We tested the effects of adding lactic acid bacteria, glucose, and formic acid on the fermentation quality and nutritional composition of A. hypochondriacus silage. The five treatments were as follows: control (no additives), lactic acid bacteria group (lactic acid bacteria added at 0.25-0.33 g/kg), glucose group (glucose added at 30 g/kg), lactic acid bacteria+glucose group (added at the same levels as in individual treatments) and formic acid group (formic acid added at 5 g/kg). Silos containing each treatment were opened on days 1, 3, 9, 30, and 57, and the pH and the contents of lactic acid, ammonia nitrogen, total nitrogen, lactic acid, acetic acid, dry matter, crude protein, and neutral detergent fiber in the ensiling samples were determined. The results showed that the additions accelerated the fermentation process. The addition of glucose and lactic acid bacteria to A. hypochondriacus silage resulted in greater fermentation, more lactic acid, and lower pH values. These additions also significantly reduced the contents of acetic acid and neutral detergent fiber and the ammonia nitrogen∶total nitrogen ratio (P<0.05), and significantly increased the contents of dry matter and crude protein (P<0.05). Adding formic acid markedly decreased the acetic acid content (P<0.05), but did not affect the dry matter content (P>0.05). We concluded that the nutritional composition of A. hypochondriacus can be preserved by making silage. Our results showed that addition of lactic acid bacteria, glucose, and formic acid can improve the quality of A. hypochondriacus silage, and that the best results were obtained by adding lactic acid bacteria and glucose.