High performance active suspension has significant advantages in improving driving experience，and robust control algorithm is an important guarantee for active suspension performance. To solve the problem that the typical robust control algorithms are difficult to achieve effective disturbance estimation and compensation，in this paper，a H₂/H_∞-H₂-IUDE algorithm is proposed to estimate and compensate the disturbance by using IUDE algorithm and introducing in H₂ state observer，which improves the robustness compared with H₂/H_∞ algorithm. Firstly，the model of half vehicle active suspension control systems is established，and the disturbance form is defined. Then，an IUDE algorithm for disturbance estimation and compensation decoupling is proposed，and a H₂ state observer is proposed to redesign H₂/H_∞ algorithm. Finally，simulation analysis is carried out for typical working conditions such as random road surface and speed bump road surface. The results show that，compared to the H₂/H_∞ algorithm，the proposed algorithm reduces the root mean square values of the vehicle body center vertical acceleration and pitch angle by 7.6% and 5.9%，respectively，under random road conditions，demonstrating a significant improvement in vehicle ride comfort. Meanwhile，the proposed H₂ observer can effectively estimate system states. The IUDE algorithm can accurately estimate disturbance，and can avoid the deterioration of suspension dynamic deflection caused by the non-decouple UDE method，which has outstanding characteristics of excellent disturbance estimation and flexible compensation.