High-pressure sodium vapor lamp with high color rendering including, in an arc tube of a light transmitting material formed in a substantially cylindrical shape sealed hermetically at both axial ends, a pair of electrodes disposed internally at both axial ends of the tube and xenon gas of at least 2.5.times.10.sup.4 (Pa) sealed in the tube together with sodium vapor, is so constituted that a lamp voltage upon lighting of the lamp and represented by V (V as a unit), lamp power represented by W (watt), internal diameter of the arc tube represented by .phi. (mm) and distance between the pair of electrodes represented by d (mm) will satisfy the following formulas: 2.0.ltoreq.V/d.ltoreq.2.7 (1) and 20.ltoreq.W/.phi..ltoreq.28 (2)