To provide a solder paste composition, which suppresses breakage of a bump and forms a bump with high yield and uniform height by a solder precoat method using a dam.

The solder precoat method using a solder paste composition 5 is carried out as follows: a dam 4 is formed around electrodes 2 on a substrate 1; an opening surrounded by the dam 4, in which the electrodes 2 are positioned, is filled with the solder paste composition 5; and the solder paste composition 5 put in the opening is heated and adhered to the surfaces of the electrodes 2, so that a solder bump 6 is formed. The solder paste composition contains solder powder, and the particle size distribution of the solder powder is as follows: particles having <10 μm diameter is ≥16%; and the total of particles having <10 μm diameter and particles having ≥10 μm and <20 μm is ≥90%.