The invention discloses a closed self-backheating semiconductor heat pump low-temperature vaporization system and method and belongs to the field of energy and power. The closed self-backheating semiconductor heat pump low-temperature vaporization system and method is characterized by comprising a raw material tank (1), a raw material pump (3), a preheating pipe (4), a crystallizer (5), a shell jacket (6), a direct-current power source (7), a semiconductor chilling plate (8), a graphite heat conduction film (9), a circulating pump (10), a screen separator (12), a condensed fluid storage tank (14), a concentrated solution pump (15), a concentrated solution storage tank (17) and a refrigerant water pipe (18). The heat pump performance coefficient of the whole low-temperature vaporization system is smaller than 1, and the low-temperature vaporization system saves energy compared with a conventional direct electric heating low-temperature evaporative crystallization system. In addition, compared with a low-temperature vaporization system adopting mechanical vapor recompression, though the closed self-backheating semiconductor heat pump low-temperature vaporization system has the low heat pump performance coefficient, the overall investment cost is also low as no compression of huge structural dimensions is adopted.