The utility model discloses an on - -spot test bituminous mixture fire behaviour's device constitutes by installing the body, the device body includes transparent box, shear strength hammer, combustion chamber, portable specimen holder and smog receiving flask, in the box through pulley and spout and combustion chamber sliding connection is located be provided with on the box directly over the combustion chamber under with the opening that the combustion chamber profile phase corresponds is provided with on the opening directly over the combustion chamber and is used for fixing the buckle of shear strength hammer, combustion chamber's bottom is equipped with combustion chamber becomes the cutting ring of a body structure, be provided with the scale that is used for observing flame height on the box, still be provided with in the box and be used for fixing a supporting beam of portable specimen holder, be provided with the thermometer on the portable specimen holder, still be provided with on the box with the breather pipe that the smog receiving flask is linked together. The utility model has the advantages of convenient operation, the test is simple, and safety ring protects.