Abstract: The precipitation behavior in grain interior of 3104 aluminium alloy during homogenization was investigated by thermal analyzer, optical microscope, scanning electron microscope and energy dispersive spectrometer. The results show that, there is no obvious precipitates in the grain interior of 3104 aluminium alloy when the homogenization temperature is 300℃. At 350 ℃, the 3104 aluminum alloy has a short rod-shaped Mg₂Si precipitate within the crystal. The number increases with the extended insulation time. At 400-500 ℃, the Mg₂Si precipitated phase size is significantly larger than that of 350 ℃.After holding at 500 ℃ for more than 5 h, Mg₂Si is basically completely dissolved. The granular Al MnSi phase is precipitated in 3104 aluminum alloy grain when the homogenization temperature is raised to 560 ℃ and held for 10 h. When the temperature reaches 630 ℃, the Al MnSi phase in 3104 aluminum alloy grain at 630 ℃ is basically completely dissolved.Considering various factors such as production cost, it is reasonable to choose the uniform temperature of 3104 aluminum alloy at 560-620 ℃, and the insulation time is about 10 h.