The influences of some agronomic properties on the chemical composition of five varieties of soybeans (namely Amsoy, Corsoy, Calland, Union, Williams grown in Turkey as a second crop were examined. According to the results of analysis of 40 soybean samples, the average contents of crude oil (as the percentage of dry matter). crude protein, total mineral matter were found as 20.01 "111,42.01"/11 and 5.64"/u,respectively.The same samples contained in average 11.3X"hi total sugar,X.24'%1 humidity,5.26"/~ crudecellulose. Fatty acid composition is as follows (as area'lki in average) palmitic acid 12.53, stearic acid 4.02, oleic acid 22.64, linoleic acid 53.71, linolenic acid 7.03. Statistical analyses related to the above mentioned factors were carried out and simple correlation between chemical constituents were also calculated. A negative correlation factor was found (r = -0.631) between total fat and protein content of soybean samples I n t r o d u c t i o n Soybean can be classified as a protein seed rather than an oilseed. The average, proximate composition of presently grown varieties is: 40(vo protein and 20% oil depending upon variety climatic conditions and strain. Protein content ranges between 34-49"h and oil content ranges from 14-25%'. Protein content in soybeans is higher than in many meat products and about twice of other food legumes. Soybean protein products are reasonably well tolerated and are of good protein value for humans of all ages and less expensive than animal proteins.Worldwide production of soybean is nearly 95 million tondyear and has been increasing at a rate about 6 % per year. Soybean production of U.S.A. was approximately 60 million metric tons in 1983, Brazil 15 million metric tons, China 9 million metric tons, Argentina 4 million metric tons and Canada 0.9 million metric tons m 1983 respectively. In Turkey adaptation trials of soybeans in various regions were begun in 1980. Since 1982 soybeans have been cultivated also as a second crop principally in mediterranean costal regions. The production has been raised to about 200 000 metric tonslyear in 1985. It is estimated that soybean production will reach one million ton per year at 1991.This research was carried out on material from five soybean varieties, namely Amsoy, Corsoy, Calland, Union, Williams whose adaptation and yield trials were run in 1981 and 1982. Taking also in consideration planting time and planting density factors, their chemical constituents were investigated. M a t e r i a l s a n d M e t h o d s Five varieties of soybeans cultivated as a second crop in