This experiment was conducted to study the effexts of seeding time and varieties on yield components, protein and oil content of soybean. Four varieties of soybean(Chung Buk Baek, Iksan, Keum doo, Chang dan Baek mok)wrere applied in this experiment and were seeded at May 15th, June 5th, and June 25th, the results obtained are as follows. 1.When the soybean was seeded at May 15th, stem height, stem diameter and number of nodes on main stem came to an end about 70days after seeding. In case that the seeding time was delayed 20 days and 40 days from May15th, respectively, the time to be almost cimpleted the growth of the characteristics was shortened 10days and 20days during ther debelopment. Among varieties, Chung Buk Beak grew faster than any other varieries. 2.When seeded at May 15th, the plants produced many pods, and had high proportion of branch pods. When seeded late, the proportion of branch pods were low. Branches had large proportion of empty pods and one grain pods, but on main stem, the proportion of two grain pods and three grain pods were more than that of branch. Among varieties, Chung Buk Baek had high proportion of two and three grain pods, Keum doo and Chang dan Baek mok had high proportion of one and two grain pods, and Iksan had high proportion of one and three grain pods. 3.Tields were less by the late seeding.The proportion if decreased yields to the yields when seeded at May 15th, that of Chung Buk Baek was decreased 6% when seeded at June 5th and 14% when seeded at June 25th, that of Ik san was decreased 9% and 17%, that of Keum doo decreased 15% and 26% and that of Chang dan Baek mik decreased 18% and 27%. 4.Protein content was highest in the plots seeded on May 15th, but oil content was highest in the plots seeded in June 25th. Among varietiesm Xhang dan Baek mok had the highest proportion of protein content and Iksan had the highest of oil content.