The invention discloses a method for screening methanol-to-olefin catalysts at low temperature, Catalyst powder is contained in a DVS instrument sample chamber, and the temperature of the sample chamber is kept 60 DEG C or below; the sample chamber is purged with inert gas, the ratio of dry air to wet air is controlled and regulated to be 98:2, the changing curve of the weight of the catalysts together with time is detected, an adsorption kinetics curve of the catalysts generated when the relative partial pressure of methanol steam is 2% is acquired, the partial pressure of the methanol steam in the inert gas is regulated by changing the ratio of dry air to wet air, changes of the weight of the catalysts are detected under different partial pressures, and an adsorption isotherm of the catalysts in the methanol steam in different concentration is acquired; the point with the maximum adsorption speed (maximum slope value) is searched for from the acquired adsorption isotherm, and the catalytic performance of the catalysts on an MTO reaction is judged. The method has the advantages of being easy to operate and high in accuracy rate when the average diolefin selectivity degree of the catalysts is judged.