A hinge device applicable to soft display module includes a joint unit assembly. The joint unit assembly has a main section, a first side, a second side and a top section. The joint unit assembly has multiple shaft guide sections and shaft fixing sections positioned on the main section and respectively assembled with the motional shafts. A rotary shaft and a socket are formed on the first and second sides of the joint unit assembly along the top section. A (soft) display module is disposed on the top section of the joint unit assembly. The shaft guide section of the joint unit assembly is defined with a first position and a second position. When operating and opening/closing the display module, the rotary shafts serve as rotational fulcrums, whereby the motional shafts are relatively rotatable between the first and second positions of the shaft guide section.