A triangular pulse signal generation scheme with variable symmetry based on a dual-polarization quadrature phase-shift keying (DP-QPSK) modulator is proposed. The triangular pulse signal with a tunable symmetry coefficient can be generated by adjusting the modulation index of two sub modulators of the DP-QPSK modulator and the phase shift of three electrical phase shifters. The tunable range of the symmetry coefficient is 0%-100%, and the repetition rate of the generated triangular pulse signal is twice the frequency of the input driving signal, which shows that a triangular pulse signal with variable symmetry and high repetition rate can be generated using a driving signal with lower frequency. The feasibility of the proposed scheme is verified through a simulation, and the similarity between the pulse waveform generated by the scheme and the ideal waveform is evaluated using the root mean square error (RMSE). The study verifies that, in addition to the triangular pulse signal, the scheme can also generate a square pulse signal.