In spite of the fact that there are many sheep breeds in Iran, few studies have been established with respect to their economical traits. Moghani sheep is one of the best Iranian meat type breeds with a 5.5 million population. Some specifications of this breed include Resistance to weather conditions, big body size and ability to producing heavy lambs. The aim of this research was to survey the environmental effects and estimates of genetic parameters for birth weight (BW), average daily gain from birth to three mounts of age (ADG1), three months age weight (TRW), average daily gain from three to six months age (ADG2), six months age weight (SIW), nine months age weight (NIW), yearly weight (twelve months age weight or TWW), lamb fleece weight (LFW) and yearly greasy fleece weight in mature sheep (YFW). The effect of birth year, ewe’s gestation period (or age for yearling greasy fleece weight), birth type and sex as fixed effect and sires (nested in years) as random effect on aforesaid traits were studied.