An analyzer analyzes a measurement sample on the basis of spectrum data obtained by irradiating light to the measurement sample. The analyzer includes a main analysis part, a correlation data storage part and a concentration calculation part. The main analysis part calculates a concentration of a predetermined hydrocarbon component contained in the measurement sample on the basis of the spectrum data of the measurement sample. The correlation data storage part stores therein a plurality of correlation data each indicating a correlation between a concentration of the predetermined hydrocarbon component or the spectrum data and a THC concentration. The concentration calculation part selects at least one correlation data from among a plurality of correlation data stored in the correlation data storage part according to the concentration of the predetermined hydrocarbon component, and calculates a concentration of the total hydrocarbon components in the measurement sample by using correlation data thus selected.