Abstract: The present invention belongs to the technical field of fluid machinery, and proposes a rotating guide vane module for hydraulic working condition adjustment and a method of assembling in a turbopump. The rotating guide vane module comprises a rotating guide vane back cover plate, a rotating guide vane front cover plate, a rotating guide vane drive gear, and rotating guide vanes. Each rotating guide vane is an integrally-formed independent component and comprises a rotating guide vane back seat, a blade, a rotating guide vane front seat, and a shaft. When the rotating guide vane module for hydraulic working condition adjustment of the present invention is used for adjusting the hydraulic working condition, a center gear rotates to drive the rotating guide vane drive gear, and then the rotating guide vanes rotate to change their opening degrees.