A lifting mechanism of a front door of a filter tip assembling machine is of a structure with the left side and the right side approximately symmetrical. Each side comprises a supporting arm, a linear guide rail slide block, a linear guide rail, a jacking block, a chain wheel and a chain, wherein the supporting arm is installed on the upper face of a main wall board of the filter tip assembling machine, the linear guide rail slide block is fixed to the supporting arm, the linear guide rail is movably installed on the linear guide rail slide block, the jacking block and a supporting block are fixedly connected with the linear guide rail which is connected with a motor through the chain and the chain wheel, and the front door is installed on the jacking block and the supporting block and moves up and down on the linear guide rail slide block along the linear guide rail. The lifting mechanism has the advantages that the structure is simple, running is stable, speed is easy to control, and safety and reliability are achieved; the automation degree and production efficiency of a cigarette production line can be improved.