The invention discloses a weather simulator utilizing a condensation method and a water pump method and a method. A weather simulator box is internally partitioned into an upper water storage box located at the upper portion of the box and a lower water storage box located at the bottom of the box through a vertically-arranged aluminum plate with holes and an organic glass plate with holes, a semiconductor chilling plate is arranged on the aluminum plate with holes, an ultrasonic atomization piece is arranged on the semiconductor chipping plate, a floating ball water level switch is arranged on a base plate of the upper water storage ox, an LED module is further arranged on the base plate of the upper water storage box, water inside the lower water storage box is pumped into the upper water storage box by connecting a first water pipe to a first water pump, water inside the upper water storage box flows downwards through the aluminum plate with the holes into the lower water storage box, the bottom of the lower water storage box is sealed by a water partition plate to form an airtight and waterproof cavity for containing a controller, and the controller comprises a single-chip microcomputer module for receiving and processing data and emitting an instruction, a relay for controlling the semiconductor chilling plate and the ultrasonic atomization piece and a drive module for controlling two water pumps and the LED module.