A portable negative-pressure device including a housing, a piston, a barrier layer and a spring means for forming a first collection chamber and a second collection chamber having a variable volume to form a pressure-reducing region is provided. In the situation of that the exudates have been stored in the first collection chamber, the portable negative-pressure device can still maintain a sufficient negative pressure by continuously compressing the piston, and the second collection chamber will provide an additional liquid storage space.
