For the advanced manufacturers with high risk costs, the paper takes the arrival time as continuous random variable and least mean of the total cost of supply and manufacturing system as objective to establishes the mean value model of each cost as supply logistics provision changes under different situations to determine the optimal supply logistics provision. It analyzes the effect of logistics profit margin to the optimal supply logistics provision for manufactures. The example shows more supply logistics provision can effectively reduce the average total cost; the total cost mean converges faster if the vehicle failure probability is less; the optimal supply logistics provision of manufacture will be less than that of the whole system due to extra high profit margin of logistics.