Aiming at high dimension and position precision requirements for radial hole on precision valve core and unstable machining quality problem,a special drilling fixture was designed with reversedgroove loading and quick clamping by eccentric wheel.The positioning and clamping scheme of the fixture was analyzed, the working principle and process were described.Through analysis and validation,the designed fixture can meet the high precision requirement for radial hole drilling. The fixture has the advantages of simple operation, strong adaptability and stable machining quality.It provides reference for the high-precision radial hole drilling of shaft parts.