Abstract: In this study, the effects of selenium enrichment on three kinds of leaf lettuce were compared. To observe the selenium-enriched influence on ‘Sheshou101’, ‘Daxiangshengyihao’, ‘Meiguodasusheng’, the content of selenium was measured by atom fluorescence spectrometer standard curve after the leaf lettuce was sprayed sodium selenate and selenite once or twice respectively with a series of gradient concentrations of 7.5, 15.0, 22.5 g/hm2. The results showed that 2 kinds of selenium source with different concentrations all can increase selenium content of 3 kinds of leaf lettuce. Of all the concentrations of both selenium sources, 22.5 g/hm2 of sodium selenite led to the best selenium-enriched effect. In once-spaying test, (11.33±1.5275) μg/100 g selenium content on ‘Sheshou101’ resulted in the best selenium-enriched effect, while (14.33±0.5774) μg/100 g on ‘Daxiangshengyihao’ contribute to the best in twice-spraying test, 3 times higher than (4.87±0.3215) μg/100 g after spraying once.