In order to study the correlation between volatile carbonyls in cigarette mainstream smoke and chemical constituents in tobacco leaves, chemical constituents (soluble sugars, organic acids, sterols, solanesols, polyphenols, alkaloids, and other routine chemical components) in flue-cured tobacco leaf samples from 5 areas in southwest China were analyzed to evaluate their effect on volatile carbonyls (formaldehyde, acetaldehyde, acetone, acrolein, propionaldehyde, crotonaldehyde, butyl aldehyde and 2-butanone) in cigarette mainstream smoke. The results showed that various secondary metabolism substances in tobacco leaves from different areas varied considerably. Among them, organic acids, polyphenols and alkaloids were relatively high, sterols were moderate, and main chemical components were well coordinating in general. For released volume of most volatile carbonyls in cigarette mainstream smoke, tobacco leaf stalk position’s order was the middle leaves > the upper leaves. In terms of different areas, tobacco leaves from area 1 and 2 released more volatile carbonyls in mainstream smoke than those from other area leaves, tobacco leaves from area 5 released the lowest volatile carbonyls in cigarette mainstream smoke, while tobacco leaves from area 3 and area 4 were placed in the middle. The correlation analysis demonstrated that both leaf carbonaceous compounds and nitrogen compounds were important precursors of volatile carbonyls in cigarette mainstream smoke. The emission of important volatile carbonyls in cigarette mainstream smoke shows a positive correlation with the contents of soluble sugars, some organic acids, sterols, potassium and starch in tobacco leaf, but negative correlation with the contents of total organic acids, solanesols, polyphenols, alkaloids, proteins and total nitrogen in tobacco leaf.