During the spawning seasons of 1958 and 1959 an experiment was conducted to compare the spawning success of channel catfish in three types of environments. The environments employed included a O.6-acre pond, 16 concrete block holding pens 6 feet wide, 12 feet long and up to 3% feet deep, and six aquaria of 50 gallon capacity along with four concrete holding house tanks. The spawning fish were from three to four years old and were in what was considered to be average flesh. The highest percentage of spawning fish was noted in the pond environment both years. Spawning success was noticeably less in the spawning pens and was lowest in the aquaria or holding tanks. A few fish in the pens were injected with a hormone preparation, chorionic gonadotropin, while all fish held in the aquaria or holding tanks were treated with either fish pituitary or chorionic gonadotropin injections. Results of the experiment indicated that the least restrictive environment gave the highest percentage of spawning success for the brood stock employed. Also, hormone injections during the spawning season did not appear to be a substitute for the development of a brood stock of mature, well-fed and healthy fish prior to spawning time.