A rotor structure of synchronous reluctance motor which includes at least one rotor sheet is provided in the present invention. The rotor sheet has a center hole and includes a plurality of reluctance units surrounded the center hole. The reluctance units have an inner through-hole pair and an outer through-hole pair. In an inner through hole of the inner through-hole pair and an outer through hole of the outer through-hole pair, an inner tangent extension and an outer tangent extension are extended along a tangent extension direction. Two oblique extensions are extended from the inner tangent extension and the outer tangent extension along a turning direction which is oblique to the tangent extension direction respectively. An oblique included angle of the outer through hole is smaller than an oblique included angle of the inner through hole.