The invention provides a natural drying preparation method of graphene aerogel. The method comprises the following steps: mixing a graphene oxide solution with a reducing agent ethylenediamine (EDA) and borax, wherein hydrogel is formed by self-assembly after a period of time of hydrothermal reaction; performing dialysis and pre-freezing for a period of time for moulding; and drying to remove moisture to obtain the graphene aerogel with sound shape and without volume shrinkage. In the invention, through the improved hydrothermal reaction and a bionic means (borate crosslinking effect) between the graphene sheet layers, the rigidity of the aerogel is enhanced, the contact angle between water and graphene is controlled, and the capillary force in the drying process is remarkably reduced. In the invention, the preparation process is simple and easy to control, the production cost is low, and batch production is easy to implement; the prepared graphene aerogel has excellent mechanical property and the like; and a technical support is provided for large-scale commercial preparation of graphene aerogel.