During successive summer seasons of 2008 to 2011, this study was conducted at Middle Delta region. Eight sweet pepper breed lines were used in half-diallel cross mating design to produce 28 F₁ pepper hybrids. The extent of heterosis was estimated based on (MP), (BP), (TP) and commercial hybrid (CH) for some palnt and fruit traits. Analysis of variance showed a great diversity and significant differences  among the studied genotypes (parents and hybrids). 13 hybrids gave better parent heterosis (heterobeltiosis) for plant height and total yield, while five F₁'s for number of branches and early yield. Relative to the top parent, seven hybrids (for plant height) and two ones (for number of branches and total yield) reflected top heterosis (TH%). None of the studied hybrids showed heterosis over MP, BP and TP for average fruit weight, fruit length and diameter, while standard heterosis (SH%) was obtained for all the studied traits. Additive and non-additive gene effects were found for number of branches and early yield. Non-additive effects were predominance for plant height and total yield, white fruit characters (weight, length and diameter) of the whole were controlled by additive effects. Based on the standard heterosis expressed by the hybrids, “B.23-5 x MAR-6" (Balady fruited type) and “L.S.5-14 x L.S.2-2" (Long fruited type) were found to be superior over the commercial hybrid and could be used  for commercial production, which must be depended on its actual high productivity and not on its average degree of heterosis.