In this, we have investigated the solute behavior in front of solid-liquid interface according to the change of the cooling rate in bronze alloy and phosphor bronze alloy. The conclusive summary is as follows: 1) The secondary dendrite arm spacing was decreased with increasing the cooling rate. 2) The minimum solute concentration happened to along centerline of primary arm, and the maximum solute concentration was found at the boundary of arm or between the arms the minimum solute concentration was increased with the cooling rate. 3) Segregation Index S was decreased with increasing the cooling rate and content of P. 4) The degree of the microsegregation was decreased with increasing the cooling rate. The effective distribution coefficient, Ke was increased with addition of P in Cu-Sn.