A printing-height increasable three-dimensional printer includes a base, an elevating shaft, an elevating platform, a first driving module, a working platform, a printing nozzle, and a second driving module. The elevating shaft is connected to the base. The elevating platform is slidably connected to the base. The first driving module is configured to drive the elevating shaft to make the base move along a direction, and is configured to drive the elevating platform to reversely move relative to the base along the direction. The working platform is slidably connected to the elevating platform. The printing nozzle is connected to the base and is configured to print on the working platform. The second driving module is configured to drive the working platform to move between the printing nozzle and the elevating platform.