The invention provides a base tire manufacturing method and a base tire having a proper thickness for the rubber layer by setting the thickness of the rubber layer in such a manner as to optimize the buffing allowance for the cure-molded base tire without placing limits on the shape of the post-buffing base tire. The base tire thus manufactured has a belt layer, an outermost rubber layer of a predetermined width disposed over the belt layer for application of a tread therto, and edge rubber members at both axial ends of the outermost rubber layer. For this base tire, the loss tangent of the outermost rubber layer is set lower than the loss tangent of the edge rubber members, the pre-buffing thickness A1 at the equator of the outermost rubber layer is set at “post-buffing thickness A2×150%” or less, and the post-buffing thickness A2 is set in a range of 1 mm to 3.5 mm.