A supporting device includes a dual-shaft hinge module and two buffering modules respectively arranged at two opposite sides of the dual-shaft hinge module. Each dual-shaft hinge module includes two shafts, a linking member clamped between the two shafts, and two side wing members respectively and slidably installed on the two shafts. The two buffering modules are respectively installed on the two shafts and are respectively cooperated with the two side wing members. Each buffering module includes an internal connecting member fixed on and synchronously rotatable with the corresponding shaft and an external connecting member slidably disposed on the internal connecting member and provided to be fixed on a carrying plate. Each side wing member has a limiting portion passing through the corresponding internal connecting member and the corresponding external connecting member.