Abstract: The quality of rapeseed is closely related to changes in rapeseed growing period.In order to obtain highquality rapeseed,Brassica different harvest to double low rapeseed yellow seeds as test material,measured their oil content,protein content,total sugar content and a variety of fatty acids and other indicators,and correlation analysis for each index.The results showed that: the nutrients accumulated,the moisture content decreased on the rapeseed maturation process; the oil content increased more rapid at the middle maturation stage,then slowed down at the later stage and reached a maximum value 35.33% at 32d; small changes in protein content,there was a certain rise in pre- mature change in the late gentle; total sugar content decreased,ranging from 13% to 8%.The oleic acid relative content in rapeseed oil increased slowly,the maximum value of 56.99%; linoleic acid and linolenic acid generally showed a slow downward trend; palmitic acid and stearic acid also changed to some extent,but changed slightly; fat content and protein content was significantly positively correlated,it was significantly positively correlated with the total sugar content; the relative amounts of the relative content of oleic acid and linolenic acid showed a significant negative correlation; the relative content of linoleic acid and linolenic acid content showed a significant relative negative correlation; the relative content of the relative content of linolenic acid and palmitic acid showed a significant positive correlation.Considering the accumulated variation of each substance,it was the best harvest time during the 29 d to 32 d after flowering.