Heritability and genetic advance of some grain yield components and some morpho-physiological traits in 36 sorghum hybrids [Sorghum bicolor L. Moench] produced by top-cross using cytoplasmic male sterility were estimated. Narrow-sense heritability for plant height and head length were relatively high in Damascus location (65% and 56%) respectively, but the narrow-sense heritability of all characters in Raqqa location were low, the range was from 3% for threshing percentage to 34% for plant height, and from 22% for seed weight/head to 60% for plant height in the combined analysis. Genetic advance estimates were relatively low for all characters, the range was from 0% for 100 seed weight to 28.3% for plant height (Damascus location), and from 0.02% for seed numbers/head to 15.2% for plant height (Raqqa location), and from 5.8% for the number of days to flowering to 26.5% for plant height (combined analysis). Some characters such as plant height and head length showed relatively high values of heritability, but exhibited low values of genetic advance. Therefore other characters had low heritability coupled with low values of genetic advance indicated predominance of non-additive gene action. This result implies the need for several generations of selection to improve grain yield components and other traits.