The aim of this research is to make a design formula for shear connection of wooden/wood-based-material dowel. This paper is mainly focused on the relationships between load-displacement characteristics of joints and slenderness-ratio of dowels. As no specific standard dimension for wood dowel, there's case wood dowels are used with short and fat shape. As a stiffness theory on those short-type dowels, friction between dowel surface and the timber hole were taken into account. And for the analysis on yield of joint, shear yield was taken into account. And as former research showed important role of scale-effect on small piece of wood, material characteristics of dowels and timbers were checked with proper sizes. The results showed good correspondences with the theories on both stiffness and yield. And consecutive design formula was organized for dowels of various types of slenderness.
