Circuit board, electronic device, and production method for circuit board

This application provides a circuit board, an electronic device, and a production method for a circuit board. The circuit board includes: a board body; an electronic component, welded to a surface of the board body by using soldering tin; and a reaction particle, disposed on the surface of the board body and adjacent to a weld leg for welding the electronic component. When the circuit board is energized and in an environment with water, the reaction particle reacts with the weld leg to form an insoluble protection layer on an outer surface of the weld leg, and the insoluble protection layer isolates the weld leg from water to prevent dendrite corrosion of the weld leg.