The purpose of this paper is to synthesize the nanoporous structure of nickel selenide by cyclic voltammetry technique on a graphite rod substrate that is active for water splitting. This is the first report of the manufacture of this morphology as impressive water splitting electrocatalyst on a graphite rod substrate using a rapid, one-step, and cost-effective electrodeposition technique. Herein, first, a graphite rod was modified with nickel selenide nanoporous by controlling the electrodeposition condition. The main outcomes reveal that the optimized Ni-Se coverage on graphite rod substrate illustrates hopeful HER acting with fewer overpotentials of −100.7, −281.3, and −552.9 mV at the current densities of −10, −100, and −400 mA. cm−2, in order. Besides, the manufactured Ni-Se nanoporous catalyst is extremely energetic into OER, needing just 268 mV overpotentials for 10 mA. cm−2 current density. This research proposes a cost-effective and fast manner for manufacturing a novel nanoporous electrocatalyst that is a very active electrocatalyst for H2 and O2 improvement reactions. These outcomes propose that electrocatalyst is capable to be used for creating renewable-resource energy in industrial usage.