This study was directed to the feasibility of applying a simple atomizer-model 4650 type I (abbrev. M)-to bronchial challenge test. 92 cases of asthma were divided into 3 groups randomly. All of them were subjected to the bronchial challenge test by M atomizer, and by standard Dosimeter atomizer (abbrev. D) as a comparison. In the test by M atomizer, the times for inspiring challenging medicine were 1, 1.5 and 2 minutes for the 3 groups respectively, while the time for D atomizer was 1 minute for all. The results showed no significant differences (P > 0.2-0.5) between the two atomizers in the 3 groups, their values were linear correlated. When the inspiring time was 1 minute for both M and D, the test needed a higher concentration of challenging medicine for M than for D, their coefficient of correlation (r = 0.285) was relatively low. When inspiring time postponed to 1.5 minute for M, the difference in medicine concentration between M and D was smallest (-0.075 g/L), r = 0.665. However, a further postponed inspiring time to 2 minute for M reversely broadened their difference. These results indicated that the efficiency of M atomizer was a little lower than that of D, postponing the inspiring time for M could make up this weakness. A 1.5 minute inspiring time for M atomizer was the suggestion. Some modifications on M atomizer were done by us for a better efficiency, and the cheap and popular M atomizer could be a good replacement in bronchial challenge test.