Introduction. The chataigne or breadnut, Artocarpus camansi Blanco, has high nutritive value but it is an under-utilised food source. Yield losses due to tree height and limited information on productivity are constraints to commercial production. Our study was undertaken to determine fruit yield and seed yield, the relationship between fruit size and seed yield, and the response of yield to pruning. Materials and methods. Fruit and seed yield data were collected from 1996 to 2002 from three seedling trees established at the University of the West Indies in Trinidad and Tobago in 1993. The trees were pruned in December 1998. Results. The highest fruit mass per tree (139.7 kg), fruit number per tree (126) and seed mass per tree (59 kg) were obtained in 5-year-old trees. Fruit and seed yields were significantly (P < 0.001) lower in the years after pruning. Fruit mass per tree was positively correlated with fruit number (r = 0.99). Seed mass per fruit was positively correlated with seed number per fruit (r = 0.87) and both variables had strong, positive correlations with mean fruit mass (r = 0.83 and r = 0.77, respectively) and fruit volume (r = 0.63 and r = 0.67, respectively). Discussion and conclusions. Chataigne fruit and seed yield potential is greater than originally estimated. Both are strongly related and selection for high seed number per fruit with more effective pollination, disease control and proper tree height management may further increase productivity. In the field, estimated fruit volume is the most practical indicator of seed yield.