Abstract: A measurement apparatus for ulcerative colitis diagnosis and prognostic test according to the present invention comprises a solution mixing unit (15) for mixing an eluent and a quinone solution, the eluent being supplied from a system including a tank (9) in which the eluent used for acid separation is stored, a pump (12) for sending the eluent, a sample injection unit (13) for injecting a sample into the eluent, and an acid separation column (14) for separating short-chain fatty acids included in the sample that is injected from the sample injection unit (13), and the quinone solution being supplied from a system including a tank (8) in which the quinone solution containing quinone and supporting electrolyte is stored, and a pump (11) for sending the quinone solution; and an acid degree measurement unit (16) for measuring the acid degrees of the short-chain fatty acids separated from the sample.