We report a 544-nm Tb3+-doped LiYF4 (Tb:YLF) laser pumped by two ∼488-nm, 2-W InGaN laser diodes in continuous-wave (CW) and cavity-dumped Q-switch operations. We obtained a CW output power of 482 mW with a slope efficiency of 43%. Cavity-dumped Q-switching generated 6-ns pulses with a pulse energy of 40 µJ at a repetition frequency of 100 Hz, resulting in the highest peak power of 6.7 kW ever reported for Tb3+-based lasers, to our knowledge. We analytically examined the influence of excited-state absorption and energy transfer upconversion on the small-signal gain of a Tb:YLF laser and concluded that their influence was negligible under our operating conditions.