The invention belongs to the field of ruin search and rescue and disaster rescue, and particularly relates to a ruin life detector for performing video detection in house ruins caused by earthquakes or fires according to a floating principle. The ruin life detector comprises an air pump, a cable guide device, a screwed pipe and a guide head, wherein the air pump and the guide head are communicated with each other through the telescopic screwed pipe the cable guide device for driving the screwed pipe to perform reciprocating motion forward and backward in a rotation mode is arranged on the screwed pipe compressed air generated by the air pump is conveyed to the guide head through the screwed pipe an air opening for spraying the compressed air is formed on the guide head the guide head is suspended or swings horizontally by a reacting force generated by the spraying of the compressed air a detecting instrument is arranged in the guide head and a cable of the detecting instrument passes through the screwed pipe and is electrically connected with a console. In the ruin life detector, by using the spraying reacting force of the compressed air, the tail end of a snake-eye system is suspended and attitude control over the tail end of the snake-eye system is realized by regulation of air pressure and auxiliary air holes on both left and right sides.
