The invention discloses an atomizing test constant-volume elastomer, which comprises an elastomer main body, an elastomer upper cover, an oil atomizer mounting seat, an oil atomizer, an elastomer sealing plate, quartz glass, a quartz glass flange and an elastomer lower cover. The atomizing test constant-volume elastomer can improve the experiment efficiency of an oil atomizer atomizing characteristic experiment considerably, increase the safety of the oil atomizer atomizing characteristic experiment and enhance the image photographing effect of the atomizing experiment, so that the accuracy of experiment analysis and the experiment quality are improved, the influences of the temperature of the atomizing test constant-volume elastomer on the oil atomizer temperature are reduced, the temperature of the oil atomizer is guaranteed to be equal to the atmosphere temperature, the atomizing characteristics of different oil atomizers can be tested and the applicability of the atomizing test constant-volume elastomer is improved.