Some reproductive features of Macrobrachium potiuna and M. olfersi females were compared, correlating brood pouch volume with the number and volume of eggs during the incubation period. These data contribute to the understanding of the diversity of reproductive strategies observed in the family Palaemonidae. Macrobrachium olfersi and M. potiuna were collected in Ratones basin, Santa Catarina Island, Brazil, and the total lengths of the ovigerous females were determined in the laboratory. The eggs were measured, and the individual fecundity was determined. Volume of the eggs, egg mass volume, and brood pouch volume were estimated. Females of M. potiuna had a mean body length of 34.9 mm, mean brood pouch volume of 71.3 mm³, mean fecundity of 35 eggs, and egg mass volume of 70.3 mm³. Macrobrachium olfersi females had a mean body length of 46.7 mm, mean brood pouch volume of 127.9 mm³, mean fecundity of 1917.2 eggs, and egg mass volume of 96.6 mm³. Differences of fecundity and egg volume in M. potiuna and M. olfersi indicate the adoption of different reproduction strategies. However, proportional egg loss and increase of egg volume during the embryogenesis reflect particularities of the reproductive process of the females in the Palaemonidae.