A foldable portable metal detector, comprising: a detection coil disk ; a waterproof circuit protecting chamber ; a circuit component comprising a circuit board ; folding fixing components ; fastening components ; an extending rod ; a BLUETOOTH module disposed on the circuit board ;and a BLUETOOTH remote control component ; wherein the BLUETOOTH module is fixedly installed on the circuit board and is electrically connected with the circuit board ;the BLUETOOTH remote control component is configured to control the foldable portable metal detector; the circuit component is fixedly disposed in the waterproof circuit protecting chamber ; the circuit component is withdrawnable from the waterproof circuit protecting chamber ; the extending rod is fixedly connected to a tail end of the waterproof circuit protecting chamber ; the extending rod is manually detachable from the waterproof circuit protecting chamber ; the circuit component is electrically connected with the detection coil disk ; brackets are disposed on the detection coil disk ; each of the brackets comprises a first through hole and a second through hole ; the fastening components comprise each a bolt and a fixing column ; connecting heads are disposed on the waterproof circuit protecting chamber ; connecting holes are on the connecting heads ; each bolt passes through a connecting hole and a first through hole associated with the connecting hole in sequence; the bolts are movably connected to the folding fixing components ; each fixing column passes through a second through hole ; the waterproof circuit protecting chamber rotates with the bolts as a rotation axis. a detection coil disk ; a waterproof circuit protecting chamber ; a circuit component comprising a circuit board ; folding fixing components ; fastening components ; an extending rod ; a BLUETOOTH module disposed on the circuit board ;and a BLUETOOTH remote control component ; wherein the BLUETOOTH module is fixedly installed on the circuit board and is electrically connected with the circuit board ;the BLUETOOTH remote control component is configured to control the foldable portable metal detector; the circuit component is fixedly disposed in the waterproof circuit protecting chamber ; the circuit component is withdrawnable from the waterproof circuit protecting chamber ; the extending rod is fixedly connected to a tail end of the waterproof circuit protecting chamber ; the extending rod is manually detachable from the waterproof circuit protecting chamber ; the circuit component is electrically connected with the detection coil disk ; brackets are disposed on the detection coil disk ; each of the brackets comprises a first through hole and a second through hole ; the fastening components comprise each a bolt and a fixing column ; connecting heads are disposed on the waterproof circuit protecting chamber ; connecting holes are on the connecting heads ; each bolt passes through a connecting hole and a first through hole associated with the connecting hole in sequence; the bolts are movably connected to the folding fixing components ; each fixing column passes through a second through hole ; the waterproof circuit protecting chamber rotates with the bolts as a rotation axis. <EOS>