The invention belongs to the technical field of membrane separation and particularly relates to a positively-charged nanofiltration membrane based on a metal organic skeleton/graphene oxide compound based on surface finish amino-functionalization and a preparing method thereof. H2N-MOF/GO is loaded on an ultrafiltration base membrane uniformly, and the prepared positively-charged nanofiltration membrane has a good effect of holding back multiple metal ion water solutions. The operation process of the method is simple, the preparation condition is mild, production cost is low, and the membrane can be produced in a batch and large-scale mode and has a good industrialized production foundation and a wide application prospect.