Abstract: A paper web cutting device of a full rotation type comprises, in combination: a rotary cutter including a shank with rotary shafts at both ends, a cutting blade affixed to the shank, with its edge inclined circumferentially relative to the common axis of the shafts, a guide ring located at the cutting starting end of the blade and having a radius of rotation equal to that of the edge, and a second guide member located at the cutting terminating end of the blade and having a volute configuration, with its radius of rotation gradually decreased from the initial value equal to the radius of rotation of the edge; and a stationary cutter having a straight edge and supported in place by pivot pins at both ends, in such a manner that, at the cutting terminating end, the edge is graded to interfere slightly with the radius of rotation of the rotary cutter edge, the edge being forced by a spring to bear against the rotary cutter.