Near infrared reflectance spectroscopy（NIRS） is a new technology which has been widely used because it can determine multiple nutrients quickly,simply,non-pollution and non-distraction in the same time.Grain starch content of 131 maize hybrids which were planted in Jilin province in 2004 was determined by using near infrared spectroscopy technology meter（model MATRIX-1,made by German Bruker Company）.The results showed that grain starch content of these maize hybrids ranges from 65.89% to 75.95%,with an average of 71.38%.