The utility model relates to a device under the testing well, in particular to high temperature test appearance is with preventing falling damage device. The device's top connection upper end is connected at thermal -insulated socle end, and top connection, the screen pipe that punches, oil pipe, plug are from last to connecting down in order, and the oil pipe intussuseption is filled with the flour sand. The utility model discloses a preventing that the high temperature test appearance from falling the well and damaging, not influencing the test, costs are salvaged to a large amount of the saving. Having overcome current high temperature test appearance and not prevented falling protection device, the well that easily falls damages, and the not enough of a large amount of salvage costs need be consumeed to the while.