The present study aimed to estimate the heritability and genetic correlation for the growth-related traits in Omani native sheep. Studied traits were birth weight (BW), weaning weight (WW), six-month weight (6MW) and yearling weight (YW). For this study, records of growth-related traits (ie body weight measured at different ages) were obtained from 2174 lambs reared at Wadi Quraiyat Livestock Research Station (WQLRS) between the period from 2008 to 2016. This phenotypic data included 2174 records for birth weight, 2151 records for weaning weight, 1792 records for six months’ weight and 1442 records for yearling weight. In addition to this phenotype data, pedigree information, dam age, year of production, sex and birth type were also recorded for each lamb. Heritability was estimated by a univariate mixed model using restricted maximum likelihood procedure, and genetic correlation was calculated by a bivariate mixed model. WOMBAT software was used for the statistical analysis. Direct and maternal heritabilities of BW, WW, 6MW and YW were estimated to be 0.16 and 0.16, 0.20 and 0.20, 0.26 and 0.09, and 0.45 and 0.03 respectively. Genetic correlations among various growth traits were positive and ranged from 0.28 to 0.94. This study showed that direct heritabilities increased with age. Selection for improving one trait would improve other traits genetically because of the positive correlation. Keywords: omani sheep, growth traits, heritability, genetic correlation, genetic maternal heritability