Disclosed is a water quality analyzer, which comprises a total organic carbon (TOC) measurement section for converting a carbon component in an aqueous sample to carbon dioxide and measuring an amount of the carbon dioxide, a conductivity measurement section for measuring a conductivity of an aqueous sample, a gas aeration mechanism for passing a degassing gas devoid of carbon dioxide gas through an aqueous sample to perform a degassing treatment of expelling carbon dioxide gas in the aqueous sample, and a control section for controlling respective operations of TOC measurement and conductivity measurement. The control section is operable, just before measuring a conductivity of a specific aqueous sample during the conductivity measurement for the specific aqueous sample, to controllably instruct the gas aeration mechanism to pass the degassing gas through the specific aqueous sample so as to perform the degassing treatment.