An attempt was made to obtain a conception rate in dogs (18 Labrador males, 4 crossbreed males and 8 beagle males) with frozen semen comparable to that obtained by the use of fresh semen and natural breeding. Data on the normality of the offspring at birth, sex ratios, birth weights and litter size were collected in tabular form for comparison. Ejaculations were collected 1-3 time/wk. The volume, color, viscosity and pH of the semen and the motility and speed of the spermatozoa was analyzed. The diluent was added and the semen frozen by the Nagase-Niwa pelleting technique. Most bitches were inseminated on days 10 and 12 of estrus. Conceptions were obtained with semen stored from 1 day-35 mo. before thawing and artificial insemination. There appears to be a negligible decrease in sperm survival after more than 8 yr storage at .apprx. 196.degree. C. This technique may be applicable to all dog breeds.