Ocean is full of low-frequency, irregular, and widely distributed wave energy, which is suitable as the energy source for maritime Internet of Things (IoTs). Utilizing triboelectric nanogenerators (TENGs) to harvest ocean wave energy and power sensors is proven to be an effective scheme. However, in random ocean waves, the irregular electrical energy output by general TENGs restricts the applications. At present, achieving regularized water wave energy harvesting relies on rather complex mechanical structure designs, which is not conducive to industrialization. In this work, we proposed a novel mechanical controlled TENG (MC-TENG) with a simple controlled switch to realize the regularization function. The structural parameters of the MC-TENG are optimized, and the optimal output voltage, output current, and transferred charge respectively reach 1684.2 V, 85.4 μA, and 389.9 nC, generating a peak power density of 38.46 W·m⁻³·Hz⁻¹. Under real water wave environment, the output of the MC-TENG is regularized and keeps stable regardless of any wave conditions. Moreover, the potential applications of the MC-TENG are demonstrated in powering environmental temperature, humidity, and wind speed sensors. This work renders a simple approach to achieve effective regularized ocean wave energy harvesting, promoting the TENG industrialization toward practical application of maritime IoTs.