A soldering system includes a track, a laying device, a boiler, a shelter, a transmission roller, a position sensor, a thermal radiation heating device, and a driving device. At least one hole is formed on the shelter, and a shape and a dimension of at least one hole on the shelter corresponds to a shape and a dimension of a DIP component. The transmission roller rotates the shelter according to a transmission speed of the track. The position sensor detects a position of a circuit board relative to the boiler. The thermal radiation heating device heats an area on a second surface of the circuit board different from a first surface adjacent to the DIP component through the at least one hole on the shelter continuously, so as to increase a temperature of the second surface when the first surface of the circuit board is passing through the boiler.