One of the obvious differences between the UHVDC with single-layer connection transmission project and the UHVDC with hierarchical connection mode transmission project is latter has two AC filter yard, which will make some differences between both connection mode′s reactive power control strategy, such as DC power runback for unfulfilled ABSMIN filter and block converter for unfulfilled ABSMIN filter.In order to solve the DC power runback control problem for unfulfilled ABSMIN filter caused by UHVDC with hierarchical connection mode, the control strategy that DC power runback for unfulfilled ABSMIN filter in different operation modes of layered side is studied and some methods are proposed to reduce the impact of another normal AC grid, such as changing control mode and reducing power loss of normal layer.The control strategy test by RTDS simulation.The simulation results show that the control strategy can solve the DC power runback for unfulfilled ABSMIN filter control problems caused by UHVDC with hierarchical connection mode.