The capacity to regenerate somaclones in numbers sufficient to produce adequate population sizes from which to select is an important component of utilizing somaclonal variation for cultivar improvement. This study was conducted to determine the genetics of regeneration ability in immature panicle culture. Rice (Oryza sativa L.) immature panicles derived from 10 cultivars, 12 F1 hybrids from a 4 ✕ 4 diallel, their F2 and F3 progenies, and 24 backcross hybrids were cultured in vitro. Significant genotypic differences in regeneration ability were found among the 10 cultivars. The U.S. cultivar Lemont possessed a higher regeneration ability, averaging 8.58 plants per panicle. In contrast, the indica cultivar IR36 had a low regeneration ability, averaging 0.14 plant per panicle. Generation mean analysis of regeneration ability revealed significant values for the estimates of dominance gene effects (d), and for additive ✕ additive (aa) and dominance ✕ dominance (dd) epistatic effects, but showed additive effects to be of minor importance. The heritability estimate calculated by parent‐offspring regression was 0.25. Since additive effects are of minor importance and the heritability estimate is low, improving regeneration abilities through hybridization does not appear practical. An initial screening within possible genotypes to identify those with inherently high regenerative abilities, such as Lemont or IRGA 409, appears to be a better alternative.