The invention discloses a dynamic adjustment method for ensuring quality of service (QoS) of a delay sensitive program under a data center environment. The method comprises the steps of setting a plurality of resource limit points for a processor and a memory, computing resource sensitiveness of each delay sensitive program needing to be executed at the resource limit point, and drawing a resourcesensitiveness plane of the delay sensitive program; assuming that one delay sensitive program and a plurality of batch programs are executed on each server node, and computing resources occupied by the delay sensitive program under the condition that the delay sensitive program meets the requirement on QoS; setting the resources occupied by the delay sensitive program; distributing the residual resources to the batch programs as required for use, and setting the resources occupied by the batch programs according to a distribution result; executing the delay sensitive program and the batch programs according to a setting result; and dynamically adjusting an execution number of the batch programs. Pressure generated by the delay sensitive program is reduced by dynamically adjusting the number of the batch programs, and thus performance of the delay sensitive program is ensured.