The research of the influence of the hydromechanical transmissions reduction ratios on the skidding tractor technical and economic indices for the «Onezhets-300» tractor with HMT in particular natural-production condition (Q=10 m3, f=0,2, Ψ=0,7 on the plant recommendation) is presented in the article. The value of the technological performance and specific fuel consumption per cubic meter of skidded wood are chosen as the effectiveness criterion. The results of the conducted research showed that the performance and the specific fuel consumption while performing cargo motion essentially depend on the value of the reduction ratio of the hydromechanical transmission mechanical part. The developed methodology allow to define the optimum reduction ratios taking into account the actual characteristics of the engine and the torque converter, soil parameters and the amount of the skidded pack.