Taking dormancy-broken seed of Monimopetalum chinense Rehd. as material， differences in germination rate， germination index， germination time lag， and germination speed of seed under different temperatures （5 ℃， 10 ℃， 15 ℃， 20 ℃， 25 ℃， and 30 ℃） and illuminances （0， 750， 2 300， 4 600， and 12 000 lx） were compared. The variance analysis result shows that there are extremely significant （P＜0.01） differences in all above indexes of M. chinense seed under different temperatures, and there are also extremely significant differences in germination rate and germination index under different illuminances， but no significant difference in germination time lag and germination speed under different illuminances. M. chinense seed can germinate under 10 ℃-30 ℃， and its germination rate under 15 ℃， 20 ℃， and 25 ℃ is significantly higher than that under other temperatures， but the difference among these three temperatures is not significant. With the increase of temperature， germination index increases firstly and then decreases， and reach the highest under 25 ℃， germination time lag decreases gradually， while germination speed increases gradually. With the increase of illuminance， germination rate and germination index increase firstly and then decrease， and reach the highest under 4 600 lx， but they are significantly lower under 12 000 lx than those under other illuminances. Comprehensive analysis shows that the optimum temperature of dormancy-broken seed germination of M. chinense is 20 ℃-25 ℃， and its optimum illuminance is 4 600 lx.