The dimensions and kernel pH of several Nigerian mangoes were measured and correlated. Thereafter, a local mango kernel (the Ikanekpo variety) was studied with respect to its physical and proximate compositions, indices of the crude fat and the fatty acid composition, amino acid profile, and the bitter principle. The proximate composition and some functional properties of the processed kernel flour were also discussed. Results showed that the linear correlation coefficient between the dimensions of an unshelled seed was higher (+0·95) than that of the fresh kernel (+0·65). The kernel had a pH between 4·8 and 5·0. However, for lengths or breadths lower than 10 cm, correlation with pH was negative. The volatile matter, crude fat and tannin contents were distinguishing features of the composition. The level of unsaturated fatty acids was about double that of the saturated fatty acids. The level of linoleic acid was about three times higher than literature values for other known varieties. Compared with standard proteins, each of six essential amino acids >70% was available. Valine was the limiting amino acid. The level of tannin (45 g kg-1) was high and 48% was extracted by a combined soaking and thermal treatment employed during flour production. Consequently, the calculated LD50 per 70 kg body weight were 0·78 kg raw kernel and 1·5 kg processed flour, respectively. The latter has potential application in the preparation of steamed solid meals for adults in a traditional Nigerian household and could also be suitable for infant formulations considering its particle size distribution. © 1997 SCI.