Abstract.-The fecundity and rate of maturity of typical Michigan largemouth bass reared in ponds at the Saline Fisheries Research Station were determined in 1980-84. The smallest mature bass we observed was 7.8 inches long and the largest immature bass noted was 8.7 inches long. For both sexes, all bass over 9.0 inches long which were 2 or more years old were mature. Female bass produced about 30,000 eggs per pound. Age had no effect, independent of female length or weight, on fecundity. Low fecundity in one year (1983) may have been due to poor growth or cool spring weather. The current 12-inch minimum size limit on largemouth bass fisheries protects an "average" Michigan bass through two spawning seasons. This degree of protection seems to be more than adequate for maintaining wild populations.