The rapid development of wireless sensor networks has led to the increasing demand for continuous energy with power consumption, which brings much attention to various energy conversion devices. Here, we demonstrate a hydrovoltaic device based on non-woven flexible substrates that significantly improved their output performance by introducing AgInZnS nanoparticles. The device has excellent electrical output performance (a drop of water can produce a voltage of approximately 0.75 V and a current of 4.2 μA for more than 12 min) and humidity sensing capability. Benefiting from the ultra-high zeta potential of the AgInZnS nanoparticles and the excellent flexibility of the non-woven substrate, the device still has a steady-state output capacity of 0.6 V at a bending angle of 60°. When the external ambient humidity changes, the device has a fast response speed of 2.4 s and can achieve skin proximity sensing and respiration monitoring. The device demonstrates the improvement in output performance with the introduction of quantum dots of hydrovoltaic nanogenerators and its potential for humidity sensing.