To provide a solder with particles which can ensure a thickness of solder even if a component is inclined and its manufacturing method.

The method for manufacturing the plate solder by melting solder material 11 mixed with metal particles (12) and stirring, solidifying and rolling it includes: a step S105 for determining an additive amount N corresponding to a value S where a distance merit obtained by the additive amount of the metal particles 12 converges when determining the diameter of the metal particle and its additive amount; a step S106 for deriving a shape at a maximum inclination of the upper component 120 overlapped on the solder 10 with particles from the distance merit S, an initial plate thickness T of the solder with particles, a narrow side length L of a square, and a warranted thickness B of the solder 10 with particles for gaining a certain life derived from an experimental value, and a step S107 for calculating the diameter D of the metal particle at the distance merit S from the inclined shape.