A forklift, a hydraulic cylinder assembly (100) and a hydraulic device thereof are provided. The hydraulic cylinder assembly (100) includes a cylinder (1) having first, second oil inlets (151, 152) and first, second oil outlets (153, 154) therein; a cylinder liner (2) disposed within the cylinder (1) and being moveable between first and second positions, and defining a first oil port (21) and a second oil port (22) therein; a piston (31) disposed within the cylinder liner (2) and being moveable between a third position and a fourth position; a first oil chamber (41) and a second oil chamber (42) are defined by the cylinder (1), the cylinder liner (2) and the piston (31), the first oil chamber (41) is communicated with the first oil port (21), and the second oil chamber (42) is communicated with the second oil port (22).