The present work was carried out in order to evaluate the general (GCA) and specific (SCA) combin- ing ability and determining the parental average hetero- sis (PH) for some characteristics of the fruit in a diallel cross of 10 parents of P. peruviana. The parents of the Narino collection were: UN03, UN14, UN24, UN26, UN35, UN40, UN43, UN45, UN48, and UN49. All the direct and reciprocal crosses were made among these introductions. In two localities of the department of Na- rino located between 1900 and 2800 masl, the diameter of the fruit (FD), weight of fruit with chalice (WFC), to- tal soluble solids (TSS), citric acid (CA), index of matu- rity (IM), and pH of the fruit juice at fifth maturity state were evaluated. The analysis of GCA and SCA was made with base in method 1 of Griffing (1956). In the TSS, both additive and nonadditive gene actions were important, being UN03 the one of greater GCA. The hybrids UN40sUN45/UN45sUN40, UN26sUN48/ UN48sUN26, UN24sUN35/UN35sUN24 and UN35sUN48/UN48sUN35 displayed the greater ef- fects of SCA. Only in WFC, the nonadditive gene ef- fects were presented. The hybrids UN24sUN48/ UN48sUN24, UN26sUN49/UN49sUN26 and UN14sUN03/UN03sUN14 had the greater value of SCA. In FD, CA, IM and pH of the juice, were not differences among the genetic type, since GCA and SCA were nonsignificant. With the exception of the CA, the other variables presented a PH equal to zero. The hybrids UN26sUN48/UN48sUN26 in TSS and UN40sUN49/UN49sUN40, UN43sUN35/ UN35sUN43, UN49sUN35/UN35sUN49 and UN24sUN35/UN35sUN24 in CA had a HP different from zero. The partial correlations were positive for FD- WFC, TSS-CA, and TSS -IM and negative for CA-IM.