Abstract: Based on the perspective of regional trade gap, and taking the foreign technology as one of the influence factors of regional trade gap ,we want to explore the inner link among foreign technology spillover impact，regional trade gap and China economic growth by using the provincial panel data from 1997 to 2010. The results showed that it exists the inverted u-shaped relation between the regional trade gap and China economic growth, and calculate its inflection point value of 2.909. When we discuss the marginal effect of regional trade gap on economic growth if associating foreign technology spillover impact with regional trade gap，the marginal effect is not only related to the size of foreign technology spillover impact，also is related to the interactions between regional trade gap and foreign technology spillover impact，and the fundamental conditions depend on the relations that they are complementary or alternative within the scope of the threshold，also we calculate the threshold value of 1.845. Then we analyzed the possible causes of the empirical results.