The L block is a vertical and horizontal joint development well network. After entering the high water cut development stage, the reserve utilization between the two vertical and horizontal well networks is uneven, and the remaining oil height is scattered. The difficulty of further stabilizing production and controlling decline is increasing year by year. In order to implement the concept of “precision development” and further achieve effective utilization of scattered remaining oil, the concept of “driving unit” in the vertical and horizontal joint development well network is proposed, which is regarded as the smallest reserve utilization unit between injection and production wells. By dividing the water drive control territory, the boundary of driving unit utilization is clarified; The pressure field of the vertical and horizontal joint development well network was solved, and the streamline integration method was applied to perform vertical and horizontal injection and production split calculations. The water content, recovery degree, and formation pressure of the driving unit between the vertical and horizontal wells were obtained; Further optimization of evaluation indicators was carried out, and cluster analysis was applied to determine the classification boundary of dynamic indicators. A dynamic classification evaluation method for the driving unit between vertical and horizontal wells was established, and the main controlling factors affecting the development effect of the classification unit were analyzed. Targeted adjustment strategies were formulated. The application of classification evaluation method guided on-site adjustment, effectively tapping into the remaining reserves of the direct flat joint development driving unit, increasing the utilization degree of the entire area by 4 percentage points, and increasing the recovery rate by more than 4.6 percentage points, achieving efficient and economic development of the well area, providing reference for similar blocks.