The present study was undertaken with the objectives to estimate the genetic parameters on growth rate traits of Rambouillet sheep. The data were obtained from the records of 7161 Rambouillet sheep maintained at Government Sheep Breeding and Research Farm, Reasi, Jammu, India. The data were spread over a period of sixteen years i.e. from 2000 to 2015. The growth rate traits were generated in the study were Average Daily Gain (0-3 months) (kg) (ADG1); Average Daily Gain (3-6 months) (kg) (ADG2); Average Daily Gain (6-9 months) (kg) (ADG3); Average Daily Gain (9-12 months) (kg) (ADG4) and Average Daily Gain (3-12 months) (kg) (ADG5). Estimates of genetic parameters were obtained by paternal half sib correlation method. The estimates of heritability for ADG1, ADG2, ADG3, ADG4 and ADG5 were 0.203±0.05, 0.250±0.06, 0.944±0.16, 0.107±0.03 and 0.447±0.10, respectively. The highest genetic and phenotypic correlations were obtained between ADG3 and ADG5. High estimates of heritability and genetic correlation of ADG3 with ADG5 indicates that ADG3 can be used as selection criterion.