The application of the pulse current electrolysis method for black chrome oxide electrocrystallization on nickel substrate, named KIEROME, has been investigated. Pulse plating parameters to optimize the optical properties of KIEROME included the bath composition, current density, plating time, and duty cycle. The bath composition was prepared with the formula of 250-300 g/l chromic acid, 10-15 g/l propionic acid and 0.5 g/l of a proprietary additive. It has been observed that the KIEROME exhibited reasonable optical properties for commercialization when the plating parameters were properly controlled : absorptance (α) of 0.944, and emittance (ε) of 0.084. Thermal aging tests associated with the changes in optical properties, surface microstructures and composition profiles were also performed by aging at 300℃ and 450℃ in air for 24 hours. The surface microstructures of the as-deposited and thermally treated KIEROME coatings were investigated using Scanning Electron Microscopy (SEM), Auger Electron Scopy (AES) and X-ray Photoelectron Spectroscopy (XPS). This study implies that the KIEROME exhibits good optical properties and reasonable thermal stability for the practical application.