Using　first　principle　calculations,　the　effect　of　Ce　with　different　doping　concentrations　in　the　network　of　Zirconium　dioxide　(ZrO2)　is　studied.　The　ZrO2　cell　volume　linearly　increases　with　the　increasing　Ce　doping　concentration.　The　intrinsic　band　gap　of　ZrO2　of　5.70　eV　reduces　to　4.67　eV　with　the　2.08%　Ce　doping.　In　4.16%　cerium　doped　ZrO2,　the　valence　band　maximum　and　conduction　band　minimum　come　closer　to　each　other,　about　1.1　eV,　compared　to　ZrO2.　The　maximum　band　gap　reduction　of　ZrO2　is　observed　at　6.25%　Ce　doping　concentration,　having　the　value　of　4.38　eV.　No　considerable　shift　in　the　band　structure　is　found　with　further　increase　in　the　doping　level.　The　photo-response　of　the　ZrO2　is　modulated　with　Ce　insertion,　and　two　distinct　modifications　are　observed　in　the　absorption　coefficient:　an　imaginary　part　of　the　dielectric　function　and　conductivity.　A　2.08%　Ce-doped　ZrO2　modeled　system　reduces　the　intensities　of　peaks　in　the　optical　spectra　while　keeping　the　peaks　of　intrinsic　ZrO2.　However,　the　intrinsic　peaks　related　to　ZrO2　completely　vanish　in　4.16%,　6.25%,　8.33%,　and　12.5%　Ce　doped　ZrO2,　and　a　new　absorption　hump　is　created.　©　2018　by　the　authors.