The invention relates to a vacuum membrane distillation (VMD) device and a method used for carrying out heat recovery effectively, comprising a membrane distillation system, a heat recovery system, a heating equipment, a vacuum equipment, a liquid circulation system, a pre-disposal system, system control and detection. The vacuum membrane distillation (VMD) device and the method can utilize low-temperature heat source, and have high heat utilization ratio, high desalinization ratio and wide application range.