The invention provides a deep oil displacement and profile control agent for an oil deposit and a preparation method thereof. The deep oil displacement and profile control agent comprises the following raw materials in parts by weight: 0.15 to 0.45 part of viscoelastic polymer particles, 0.2 to 0.4 part of a chemical crosslinking agent capable of reacting with amide radical or carboxylate radical, and 99.15 to 99.65 parts of water with the degree of mineralization of 0 to 30000 mg/L. According to the deep oil displacement and profile control agent, after a mixture system of the viscoelastic polymer particles and the chemical crosslinking agent is injected into the oil deposit, the viscoelastic polymer particles and the chemical crosslinking agent are subjected to chemical cross-linking reaction at the oil deposit temperature, so that a gel system with high viscoelasticity and high strength is produced. Compared with the existing deep oil displacement and profile control agent, the system has the advantages that the system has a pore and pore throat plugging performance of the viscoelastic polymer particles when the viscoelastic polymer particles pass a stratum, further has the characteristics of high viscosity and high viscoelasticity of a crosslinking polymer gel system, has good profile control effect on oil deposits with high anisotropism degree, and meanwhile has the function of improving the oil displacement efficiency.