The invention provides an extra-cavity anastomotic method. The extra-cavity anastomotic method includes enabling two broken ends of a hollow organ to be anastomotic to penetrate from intermediate through holes from a nail bin and a base relatively and reversely overturning outwards to
expose the anastomotic positions of the two broken ends, sewing the anastomotic positions of the two broken ends by sewing nails and excising the residual ectropion part of the hollow organ by a rotary cutter. The invention further provides an ectropion type extra-cavity anastomat. An outer casing is a three-way
pipe, a nail bin is fixed in a nail bin connecting
pipe, the base and the nail bin are coaxially and relatively arranged, and the axes of the nail bin and the base are parallel to the axis of a base connecting
pipe; the nail bin and the base are annular, a
ring cutter is mounted in the nail bin and embedded in the end face of the nail bin and can axially move in the nail bin, and the end face of the base is provided with a ring slot matched with the
ring cutter. The nail bin and the base are not coaxial with the outer casing, the two broken ends of the hollow organ to be anastomotic conveniently penetrate the intermediate through holes of the nail bin and the base, and extra-cavity
anastomosis is realized.