A run flat tire which comprises a ply layer (4) disposed extending toroidally between a pair of bead cores and comprising ply coating rubber and ply cords, an inner liner layer (5) disposed circumferentially at an inner side of the ply layer, side reinforcing rubber layers (6) having an approximately crescent-shaped cross section and disposed in side portions of the tire between the ply layer and the inner liner layer and rubber sheets (7) disposed extending at interface of the ply layer and the side reinforcing rubber layer, wherein relations of t 90 >t p10 and t 10 s90 are satisfied when characteristic values of vulcanization obtained in accordance with JIS K6300-2 are represented by t p10 and t p90 for the ply coating rubber, t s10 , and t s90 for the side reinforcing rubber and t 10 and t 90 for the rubber for a sheet. Run flat durability is increased by suppressing crack growth in the side reinforcing rubber layer having an approximately crescent-shaped cross section and increasing peel strength between the ply coating rubber and the side reinforcing rubber, using a general purpose rubber.