This study was conducted to determine the equations for body weight measurement of 143 broodmares of three breeds (French Trotter, Selle Francais and Thoroughbred) using the multiple linear regression and compare it with the Martin Rosset body measurement technique. Results revealed that the accuracy of the equations by breed was close to Martin Rosset equation with a slope not significantly different from 1 in the line of identity plots for both models. It is concluded that the first prediction equation of the body weight of mares by breed confirm the Martin Rosset equation. However, the size of the sample is still small and the results should be further confirmed.