Abstract: A wearable leak-proof breast suction device is provided. The breast suction device includes a breast suction device body. A breast suction cover is disposed on the breast suction device body. A sucker is disposed on a central bulging part of the breast suction cover, and a central depression part of the sucker has a through hole connected to a three-way member of the breast suction device body. The sucker covers a breast when the breast suction device body is in operation. A connecting pipe is disposed between the sucker and the breast suction cover, and is connected to a through hole and extends in a direction toward the three-way member. Each of the connecting pipe, the sucker and the breast suction cover is flexible. An inner edge of the connecting pipe is curved at a connection with an edge of the through hole of the sucker.