It was suggested in my previous study published in 1968 that higher fertility should be obtained in oviposition before noon when hens were inseminated at early 3 to 5 o`clock. The present experiment was carried out to reexamine my previous study, and 350 hens and 1576 eggs produced by them were used for this experiment. The method of insemination used was to deposit 0.04 ㎖ of undiluted mixed semen, once for each hen, about 2-3 ㎝ deep into vagina. Hens were inseminated at seven different times of the day begining from 11 o`clock p.m., and the fertility of hens inseminated at different time was observed. The results obtained are summarized as follows; The fertility on the day following insemination was 58.3% for 11 p.m. lot, 78.8% for 1 a.m. lot, 81.3% for 3 a.m. lot, 54.8% for 5 a.m. lot, 41.9% for 7 a.m. lot, 24.2% for 9 a.m. lot, 0% for 11 a.m. lot. Higher fertility was obtained in 3 a.m. on the day following insemination proving that interval from insemination to oviposition or to ovulation should be larger than 3-5 hours. It appeared that oviposition after a pause took place at around 7 a.m. in most cases. In case of insemination after oviposition, no fertile egg was obtained on the day following insemination. The average fertility during a week following insemination was 53.3% for 11 p.m. lot, 61.6% for 1 a.m. lot, 71.7% for 3 a.m. lot, 64.4% for 5 a.m, lot, 58.6% for 7 a.m. lot, 56.2% for 9 a.m. lot, 50.7% for 11 a.m. lot, also showing the highest fertility in 3 a.m. lot. The cause of higher fertility in 3 a.m. lot was same as that in the fertility on the day following insemination.