The utility model provides an outdoor waterproof electric power cable connecting device through upper end cover, bottom end cover and sleeve shape one -tenth confined space, has good waterproof sun -proof effect, set up four through -holes that are used for outdoor cable to pass through along circumference on the telescopic outer wall, through -hole department is provided with the rubber buffer, has further promoted the waterproof ability of this device, the utility model discloses when connecting, can select two different through -holes according to actual conditions to realize the connectionbetween different two outdoor cable that move towards, furthermore, the utility model discloses when using, only need peel off the insulating layer with outdoor cable's link and directly pass in thethrough -hole, outdoor cable gets into the electrically conductive passageway that corresponds with this through -hole, two outdoor cable passes through the electrically conductive connection is realized to electrically conductive frame, and the connected mode is simple, and it is fixed that position through rotatory upper end cover makes pressing shaft compress tightly outdoor cable's wiring end,prevents that the condition of short circuit from appearing.