A lighting controller of a lighting device for a vehicle comprising: M (M is an integer of one or more) switching regulators for supplying driving currents to first to Nth (N is an integer of two or more) semiconductor light sources; first to Nth current driving means comprising: first to Nth current detecting portions (R SH) connected to the semiconductor light sources and serving to detect the driving currents respectively; and first to Nth switching portions connected to the semiconductor light sources respectively, wherein the first to Nth current driving means operates the switching portions corresponding to magnitudes of the driving currents detected by the current detecting portions (R SH) respectively; characterized in that a temperature detector for detecting a temperature and sending a temperature detecting signal when the detected temperature is equal to or higher than a prespecified temperature; and control means for controlling the current driving means in order to decrease the driving currents to be supplied to the semiconductor light sources upon receipt of the temperature detecting signal, wherein the control means sets a priority of each of the semiconductor light sources for decreasing the driving current and decreases the driving current starting from a decrease starting temperature for each of the semiconductor light sources in order from the semiconductor light source having a highest priority, wherein the priority is set based on thermal environment information including information about a preset heat resistance of each of the semiconductor light sources. M (M is an integer of one or more) switching regulators for supplying driving currents to first to Nth (N is an integer of two or more) semiconductor light sources; first to Nth current driving means comprising: first to Nth current detecting portions (R SH) connected to the semiconductor light sources and serving to detect the driving currents respectively; and first to Nth switching portions connected to the semiconductor light sources respectively, wherein the first to Nth current driving means operates the switching portions corresponding to magnitudes of the driving currents detected by the current detecting portions (R SH) respectively; characterized in that a temperature detector for detecting a temperature and sending a temperature detecting signal when the detected temperature is equal to or higher than a prespecified temperature; and control means for controlling the current driving means in order to decrease the driving currents to be supplied to the semiconductor light sources upon receipt of the temperature detecting signal, wherein the control means sets a priority of each of the semiconductor light sources for decreasing the driving current and decreases the driving current starting from a decrease starting temperature for each of the semiconductor light sources in order from the semiconductor light source having a highest priority, wherein the priority is set based on thermal environment information including information about a preset heat resistance of each of the semiconductor light sources. first to Nth current detecting portions (R SH) connected to the semiconductor light sources and serving to detect the driving currents respectively; and first to Nth switching portions connected to the semiconductor light sources respectively, wherein the first to Nth current driving means operates the switching portions corresponding to magnitudes of the driving currents detected by the current detecting portions (R SH) respectively; characterized in that a temperature detector for detecting a temperature and sending a temperature detecting signal when the detected temperature is equal to or higher than a prespecified temperature; and control means for controlling the current driving means in order to decrease the driving currents to be supplied to the semiconductor light sources upon receipt of the temperature detecting signal, wherein the control means sets a priority of each of the semiconductor light sources for decreasing the driving current and decreases the driving current starting from a decrease starting temperature for each of the semiconductor light sources in order from the semiconductor light source having a highest priority, wherein the priority is set based on thermal environment information including information about a preset heat resistance of each of the semiconductor light sources.