A study of the tensile properties of weft knitted fabric reinforced composites is presented. The rib stitch of basic weft knitted structure has been adopted in which the face and back structure is the same. The tensile strength in wale direction is higher than that in course direction in weft knitted fabric reinforced composites. It is found that the tensile strength increased in wale direction by stretching of knitted fabric before molding. Two fracture modes were suggested ; that is fracture occurs at the section with extreme low fiber content corresponding to the arc part of knitted loop in course direction and fracture occurs due to stress concentration at loop interlocking region in wale direction.