Headed studs are exclusively used as shear connectors in various steel-concrete composite constructions. The directions of concrete placing in relation to stud connectors in fabrication of composite constructions influence static and fatigue strength of studs and the composite action between steel and concrete. They can be classified to four cases. In most of the past studies, however, the effect of directions of concrete placing have not been sufficiently given consideration except the one by J. W. Fisher. The present paper discusses the effects based on the results obtained by push-out type test series and proposes design formulas for static and fatigue strength of stud shear connectors.