With the application of single-phase converter, the single-phase phase-locked loop (PLL) has received widespread attention. In this article, a single-phase self-feedback PLL (SF-PLL) is proposed, which constructs an orthogonal voltage signal by utilizing its own outputs. In addition, a low-pass filter is applied to filter out the harmonics of voltage v(q), which can improve the steady-state performance of proposed SF-PLL. The mechanism, characteristics and parameter design method of the proposed single-phase SF-PLL are introduced in detail. Compared to the traditional second-order generalized integrator PLL (SOGI-PLL), the proposed single-phase SF-PLL is simpler and has superior dynamic and steady-state performance under grid disturbance. Finally, the effectiveness of the proposed singlephase SF-PLL is validated by simulation and experiment.