The paper studies the influence of controllable hybrid reactive power compensation (HRPC) on the transient characteristics of transmission lines. Based on an analysis of the structure-function of controllable hybrid reactive power compensation, and considering the Jindongnan-Nanyang-Jingmen UHV demonstration line, an equivalent model of a single-phase ground fault of a UHV hybrid reactive power compensation line is established, and the influence of TCSC+TCT controllable hybrid reactive power compensation on the breaking characteristics of the circuit breaker is studied. Based on the Laplace transform and equivalent parameter concentration circuit, the influence factors of transient recovery voltage (TRV) are analyzed, and the variation rule of TRV with compensation degree of controllable hybrid reactive power compensation is obtained. Using PSCAD/EMTDC, the effect of the controlled hybrid on the TRV is studied, and the validity of the analysis method is verified. The results show that the TRV peak and RRRV increase with the increase of compensation degree of controlled HRPC; TCT has little effect on transient recovery voltage.