Malaria is a serious public health problem, the control of which involves actions directed against its vector, mosquitoes of the genus Anopheles Meigan, 1818. The study of insect biology, ecology, and behavior is simplified when these insects are maintained at the laboratory. However, many of the species are eurygamic and require induced mating. Females of Anopheles marajoara Galva˜o e Damasceno, 1942 were collected at Mazaga˜o county, State of Amapa´ , Brazil. F1 eggs were obtained through forced oviposition and raised until mosquito emergence. Around 300 mosquitoes were maintained in each cage and were fed with a 10% sugar solution. Induced mating was made to obtain the other generations. Females had their spermathecae examined for the presence of sperm. The efficacy of coupling in each generation was evaluated. The viability of a sample of generations F5, F9, F12, and F14 was followed from larvae to adult. Two free mating attempts were done. The results demonstrate adaptation of An. marajoara to laboratory conditions over 21 generations, with viability rates temporally increasing. There was no evidence of adaptation to free mating.