The invention provides a process for cold extrusion forming of a one-way device spline sleeve. The process comprises the steps of utilizing hollow pipes to serve as raw materials, performing blanking according to specified dimensions, sequentially performing annealing, head flattening, shot blasting, phosphatization and saponification treatment, cold extrusion shaping, cold extrusion spline forming, machining, quenching, tempering, shot blasting, cleaning and grinding machine processing, and obtaining finished product one-way device spline sleeves. The one-way device spline sleeves obtained through the process are high in precision, small in individual differences, good in strength performance and long in service lives.