Abdullah Bin Arif, S. Sujiprihati and M. Syukur. Estimated of Heterosis and Heterobeltiosis in Six Genotypes of Chilli Using Full Diallel Crosses Analysis. Until now productivity of Chili in Indonesia is still low. One effort to increase productivity of chilli is by breeding program. There are several cross designs to choose inbred lines to produce new varieties superior, including the design of cross dialel. The aims of this research were to obtain information heterosis and heterobeltiosis from hybrid of six inbred line combination and to gain candidate of hybrids superior. The research was conducted in November 2008-May 2009 at the Garden Experiments Lwikopo IPB. Genetic material used are six inbred lines of Chili (IPB C2, IPB C9, IPB C10, IPB C14, IPB C15 and IPB C20) and F1 of the hybridization of combination six inbred lines. The crossing design used was diallel cross. The results showed that population of F1 resulted from crossing of IPB C2 x IPB C10 and IPB 10 x IPB C2 had high dicotomous that was relatively higher than those of other hybrids. The population of F1 obtained from crossing IPB C2 x IPB C14 and IPB C14 x IPB C2 had weight per fruit that was relatively higher than those of other hybrids. Heterosis and heterobeltiosis values in F1 of IPB C2 x IPB C10, IPB C2 x IPB C14, IPB C2 x IPB C20, IPB C10 x IPB C2 and IPB C14 x IPB C2 were positive on high dicotomous character. Heterosis and heterobeltiosis values in F1 IPB C2 x IPB C14 and IPB C14 x IPB C2 were positive on weight per fruit character. The population of F1 that were appropriate used in breeding program to make superior variety were hybrids of IPB C2 x IPB C14 and IPB C14 x IPB C2.