The first egg laying day of White Leghorn hen which was hatched is the long-day season, May, June, and July, is over than 180 days(general standard) and it`s egg production rate is low, although the hen is fully motored. This experiment was conducted to gee the increase of phosphoprotein, vitellin, by feeding diethylstilbestrol on layer and the increase of calcium and phosphorus absorption from feeds through mucous membrane of small intestine by feeding vitamin D₂. Owing to the short-daylight, cloud, fog, and rain, winter has less ultraviolet ray. Because of the above reason, this experiment was practiced 30days in winter. Results : There were no significant differences between the number of laid eggs, total weight of laid eggs, body weight, and the amount of feed take of the experiment group and that of the control group. Although the aim of this experiment was to increase the egg production, there were no effect. We found three difficulties in this experiment: experiment term was too short, ability of used hen was too low, and the number of used hen was too few to get the definite result.