The invention discloses a process for treating fermented waste gas of amino acid by utilizing a spray cooling method. The fermented waste gas is conveyed to a gas-liquid separator by a fan, the separated wastewater with high COD enters a mash tank for recycling, gas enters a spray tower, and the condensed low-temperature gas enters the next working procedure through the upper part of the spray tower; the lower part of the spray tower is provided with a water tank, spray water subjected to temperature rise preliminarily filters solid purities obtained by the washing during the spraying in the water tank, then the filtered spray water enters a heat exchanger after the filtration through a filter to perform heat exchange with cooling water produced by a cooling tower, and the spray water is sent into the spray tower after the temperature of the spray water is reduced once again; and the produced condensed water and the spray water are mixed during the temperature reduction, then are drained out of the water tank, and are sent into a wastewater treatment plant. The process is simple, has convenient operation, ensures that the condensed water can be repeatedly used, has no problem of secondary pollution, and solves the technical problems of high water vapor content and large subsequent process load in the gas treated by the prior art.