Genetic parameters for birth and 240-day weaning weights in Gudali and Wakwa cattle breeds in a tropical environment in Cameroon were estimated by derivative-free restricted maximum likelihood procedure using singletrait animal models with maternal effects. Performance data covered the period 1971 through 1985. Heritability estimates for direct effects of live weights at birth and weaning were 0·39 (s.e. 0·10) and 0·27 (s.e. 0·09) in Gudali cattle and 0·65 (s.e. 0·15) and 0·29 (s.e. 0·13) in Wakwa cattle, respectively. Corresponding heritability estimates for maternal effects were 0·06 (s.e. 0·06) and 0·20 (s.e. 0·09) in Gudali cattle and 0·22 (s.e. 0·08) and 0·27 (s.e. 0·12) in Wakwa cattle. Estimates of genetic correlations between direct and maternal effects were negative and substantial for birth weight in Gudali (0·86) and Wakwa (-0·93) and for weaning weight in Gudali (-0·68). The estimate for weaning weight in Wakwa (-0·39) was lower. It was evident from the results that selection on individual performance was likely to yield substantial genetic progress in these traits. Although heritability estimates for maternal effects were low, the negative direct-maternal genetic relationships indicated that selection for these traits should not ignore the maternal component.