The invention discloses a soluble non-woven fabrics at a low temperature of 40 DEG C and a manufacture method thereof. The non-woven fabrics are prepared by thermally rolling soluble polyvinyl alcohol short fibers as raw material. The manufacture process comprises the following steps: primarily loosening the fibers; finely loosening the fibers; combing; netting; laying air for netting; calendaring; tidying into rolls; and rewinding and detecting and inserting a thermal rolling and molding step between the laying air for netting technological step and the calendaring technological step. The non-woven fabrics avoid using a polyvinyl alcohol adhesive as a bond, lessen environmental pollution, lower the dissolving temperature of the non-woven fabrics to the low temperature of 40 DEG C from the prior high temperature of 80 DEG C, save energy sources and water consumption and effectively overcome the defect that high-grade fashions in clothes or other embroidery products are easy to fade and deform. The thermal rolling and molding step in the manufacture process substitutes four steps in the prior process, namely gumming, pumping, drying and baking so as to shorten the flows and improvethe efficiency.