A simulation model is formulated to evaluate productivity of the cattle on an imaginary farm. The model is designed to establish an effective system covering the cattle production through fattening of calves from beef cattle. Efficiency of the modified conventional production technique is examined by increasing the conception rate of breeding cows and shortening the calving interval. It is proposed that the modified conventional method be combined with a new technique which employs an embryo transfer treatment to produce twins in an artificial way. The results based on the proposed model suggest that there be a potential for improving productivity of beef cattle with such a combined method.