A semiconductor laser device that is configured for use for optical analysis, the semiconductor laser device comprising: a semiconductor laser element ; a temperature detecting element that is configured to detect temperature of the semiconductor laser element ; an output terminal (T1, T2) that is configured to output an output of the temperature detecting element to an outside; a wire (L1, L2) that electrically connects the temperature detecting element and the output terminal (T1, T2); and a heat capacity increasing part that is provided interposed between the temperature detecting element and the output terminal (T1, T2) and contacts with at least a part of the wire (L1, L2) to increase heat capacity of the wire (L1, L2), and the semiconductor laser device further comprising: a sub-mount in which the semiconductor laser element is provided on the upper surface; and a cooling mechanism that is mounted with the semiconductor laser element and for cooling the semiconductor laser element ; and a control part (COM) that is configured to use detected temperature by the temperature detecting element to control the cooling mechanism, wherein the sub-mount is provided interposed between the cooling mechanism and the semiconductor laser element , wherein part of the wire (L1, L2) is embedded in the sub-mount , and the sub-mount functions as the heat capacity increasing part . a semiconductor laser element ; a temperature detecting element that is configured to detect temperature of the semiconductor laser element ; an output terminal (T1, T2) that is configured to output an output of the temperature detecting element to an outside; a wire (L1, L2) that electrically connects the temperature detecting element and the output terminal (T1, T2); and a heat capacity increasing part that is provided interposed between the temperature detecting element and the output terminal (T1, T2) and contacts with at least a part of the wire (L1, L2) to increase heat capacity of the wire (L1, L2), and the semiconductor laser device further comprising: a sub-mount in which the semiconductor laser element is provided on the upper surface; and a cooling mechanism that is mounted with the semiconductor laser element and for cooling the semiconductor laser element ; and a control part (COM) that is configured to use detected temperature by the temperature detecting element to control the cooling mechanism, wherein the sub-mount is provided interposed between the cooling mechanism and the semiconductor laser element , wherein part of the wire (L1, L2) is embedded in the sub-mount , and the sub-mount functions as the heat capacity increasing part . a sub-mount in which the semiconductor laser element is provided on the upper surface; and a cooling mechanism that is mounted with the semiconductor laser element and for cooling the semiconductor laser element ; and a control part (COM) that is configured to use detected temperature by the temperature detecting element to control the cooling mechanism, wherein the sub-mount is provided interposed between the cooling mechanism and the semiconductor laser element , wherein part of the wire (L1, L2) is embedded in the sub-mount , and the sub-mount functions as the heat capacity increasing part . <EOS>