A device for testing the burning rate of the liquid substance is characterized in that a heating device is provided, the side wall of the heating device is installed with a heating device digital-controlled thermometer and a heating device switch, the right side of the top of the heating device is installed with a sample groove and the left side is installed with a bracket with adjustable height,the bracket is connected with an igniter which is composed of two connecting rods and an igniting head, two conducting wires are respectively connected with the output end of the ignition controller and the top of the ignition controller is installed with the ignition controller switch. The invention judges the burning fatalness of the liquid substance by testing the temperature value of the liquid substance in a certain burning rate, and avoids the problem that the flashpoint value obtained from different flashpoint test methods deviates largely thereby cannot judging the burning fatalness of the liquid.