Highly branched cross-linked polysiloxane and waterproof agent

The invention relates to highly-branched cross-linked polysiloxane and a waterproof agent, which are prepared by the following steps: by taking 100 parts of a linear body and 0.5-10 parts of an amino coupling agent as raw materials, under the action of a basic catalyst, heating to 70-120 DEG C, carrying out a prepolymerization reaction for 1-5 hours, adding modified silicon resin, and carrying out a vacuum decompression reaction for 1-10 hours to obtain the highly-branched cross-linked polysiloxane, specifically, 0.01-0.1 part of the basic catalyst and 10-100 parts of the modified silicon resin. The modified silicon resin is introduced as a crosslinking monomer, on one hand, the modified silicon resin is a modified organic silicon resin which is terminated by an epoxy group, a long-chain alkyl group and a siloxane group after a monomer with four functional groups is polymerized, and the modified silicon resin has a double-layer three-dimensional compact spherical structure and is high in hydrophobicity; in ad