This paper mainly studied the photo-hydrogen production capability of using enzymatic hydrolysate to four different energy grasses, king grass, witchgrass, grassiness and alfalfa, as substrates. The cumulative hydrogen production and hydrogen production rate were taken as the indexes to contrast photo-hydrogen production capability of different energy grasses. Then modified Gompertz equation was used to perform regression analysis of hydrogen production process, and the technical feasibility using energy grasses as raw materials for photo-hydrogen production was verified. The results showed that among these four energy grasses, the hydrogen producing capability of alfalfa was the best followed closely by king grass, and the hydrogen producing capabilities of witchgrass and grassiness were feeblish, in the circumstances of 30% inoculum size, 30℃, 2000lx illuminance, 120h of fermentation time. The cumulative hydrogen production of king grass, witchgrass, grassiness and alfalfa was respectively 75.3, 27.2, 26.1, and 81.6mL. The maximal hydrogen production rate was 7.83, 3.5, 4.33, and 14.75mL/(h?L) respectively.