The escalating threats of marine pollution and climate change underline the critical need for deploying water quality sensors in oceanic environments. Recent advancements in energy harvesting technologies have been pivotal in augmenting the life span and durability of these sensors. Notably, triboelectric nanogenerators (TENGs) emerge as a promising solution due to their ability to convert mechanical energy into electricity. However, the performance of TENGs in marine settings is hampered by inherent challenges: their high internal resistance and low current generation significantly limit power output. This limitation is further exacerbated by the ocean’s inherently chaotic energy landscape, characterized by low-frequency movements. Addressing these constraints is vital for optimizing TENGs’ utility in robust, long-term ocean monitoring applications. This work introduces the design and prototype of a rolling mode TENG (MO-TENG) for harnessing ocean wave energy, utilizing multi-tunnel grating electrodes and the opposite-charge-enhancement effect. The proposed MO-TENG exhibits impressive output performance and durability. The techniques and strategies detailed in this research have unveiled fresh possibilities for the development and utilization of TENGs in marine IoT applications.