A straight-pole sun umbrella hand-cranking device comprises a standing pole and a shell fixed on the standing pole, wherein the shell comprises a first outer shell and a second outer shell. The shell is fixed on one side of the standing pole, and a rope winding wheel is mounted within the first and the second outer shells. The rope winding wheel is connected to a cranking shaft, and the cranking shaft is propelled to rotate through a cranking handle connected with the cranking shaft. An anti-slip mechanism is arranged on the cranking shaft. The anti-slip mechanism comprises a torsion spring, the torsion spring is sleeved on the cranking shaft. The rope winding wheel achieves easy winding or unwinding of the ropes, and the anti-slip performance is improved by the elastic force of the spring. As the aforesaid structure is protected against abrasion, its functional life is significantly prolonged.