The study was conducted to obtain some environmental and genetic information for sheep performance-testing, selection, and making quantitative statements about other experimental result in sheep. The environmental and genetic parameters estimated in the study were effects of some factors due to permanent differences on wool production and repeatabilities for wool production in sheep. The results were summarized as follows : 1. Significant (P$lt;0.01) differences were detected for greasy wool weights among ages of ewes at shearing. The effects of years of shearing were estimated -0.41∼0.40㎏ in Corriedale and -0.48∼0.44㎏ in Polwarth. The constant estimates of ages of ewes at shearing were -0.70 ㎏ in one year, -0.20 ㎏ in two-year and 0.32∼4.40㎏ in above-two year in Corriedale and -0.95㎏ in one-year, 0.13 ㎏ in two-year and 0.40^0.42 ㎏ in above two-year in Polwarth. 2. Estimate repeatabilities for greasy wool 0.74 in Corriedale, and 0.51 in Polwarth.