Connectedness is a statistical approach that could help breeder, under specific animal breeding situations in better deciding for animal selection from different environment. The accuracy of the comparison between EBVs from different herds depends upon the degree of connectedness between them. In this study, for considering effect of genetic connectedness effect on the genetic evaluation, comparisons of estimated evaluations and genetic parameters in two cases lack and un-lack (GC) and identification of (CR) between herd(s), birth weight (BW), weaning weight (WW) and staple length (SL) traits have been written in the C++ language program by simulation method in sheep herds with consideration of natural conditions (fertility percent, mortality percent ...). It is argued that connectedness increases as the proportion of offspring from common sires. It is very high if the 100% of the offspring in both herds are from common sires. Connectedness ratings were higher for highly heritable traits and lower for traits with low heritability.