The present invention relates to a test method for carbon dioxide in active lime, and an apparatus. The apparatus comprises: a spiral lifting bracket, a furnace, a base, a quality control box, a power supply regulator, a weighing display instrument, a temperature controller and a temperature sensor, wherein an electronic balance is arranged in the quality control box, the electronic balance and the weighing display instrument form a circuit connection, a crucible support rod penetrates through a through hole and extends into the furnace hearth of the furnace, and the top end of the crucible support rod is provided with a crucible tray. The test steps comprise: (1) calibrating the electronic balance; (2) placing 1 g of a lime sample into the crucible, and recording the stable-state mass m1; (3) heating to a temperature of 150 DEG C, maintaining the temperature for 1 h, and recording the mass m2; (4) heating to a temperature of 750 DEG C, maintaining the temperature for 1 h, and recording the mass m3; (5) heating to a temperature of 1050 DEG C, carrying out constant temperature calcination for 1 h, and recording the mass m4; and (6) calculating contents of carbon dioxide, impurities and water. According to the present invention, the automated operation of the active lime carbon dioxide test is achieved, the human error is avoided, and the accuracy of the measurement result is improved.