Metal-organic framework (MOF) is a new type of inorganic-organic hybrid porous material composed of organic ligands bridging metal ions, and it has the characteristics of tunable functions, good stability and porosity. In this study, Zn doped Co-based metal organic frame works single-crystal samples\left(\rmC\rmH_3)_2\rmN\rmH_2\right\rmC\rmo_1-x\rmZ\rmn_x \left\rmH\rmC\rmO\rmO\right_3are synthesized by the solvothermal method with normal ratio x = 0, 0.1, 0.2, 0.3, 0.4, 0.5. Single crystal diffraction, scanning electron microscope and energy dispersive X-ray spectroscopy results show that Zn ions are uniformly doped into Co-based MOFs crystals. The field cooling curves show that antiferromagnetic phase transition temperature of Co-based MOFs decreases from 15 K for pure Co-MOF x = 0 to 12.8 K for x = 0.2. Abnormal large magnetic hysteresis is obtained for Zn doped crystals with large coercive field 3600 Oe (x = 0.3) compared with 450 Oe coercive field for pure Co-MOF (x = 0), and the hysteresis area of Zinc-doped sample is more than 3 times that of pure cobalt sample. On the other hand, we find a series of steps on the hysteresis loop of DMCo_0.9Zn_0.1F sample, which gradually disappears with the increase of temperature, similar to the quantum tunneling phenomenon of a single molecule magnet. Previous studies have shown that the long range magnetic interaction and the magnetic single-ion behavior competition coexist in these systems. It is believed that the doping of non-magnetic zinc ions weakens the long-range interaction between Co ions and makes Co ions show the step effect caused by quantum tunneling at low temperature.