Effects of addition of sintering aids on sintering of aluminum, Al-Si-Cu-Mg-Fe alloy and aluminum bronze were investigated. The addition of AlF₃-KF is effective in case of aluminum sintering but not effective in case of Al-Si-Cu-Mg-Fe alloy. It is considered that the surface oxide of the powder is removed by the eutectic reaction with the sintering aids for aluminum, but that the formation of high melting MgF₂, which is the reaction product of KF and Mg, prevents the sintering of Al-Si-Cu-Mg-Fe alloy. The addition of AlF₃-KF was found to reduce the sintering temperature for aluminum bronze although AlF₃ alone is an effective sintering aid.