Reliability of a semiconductor device is improved. A first pad electrode is formed in an uppermost layer of a multilayer wiring layer, an insulating film of a non-organic material is formed over the first pad electrode, and an organic insulating film is formed over the insulating film. In the organic insulating film, an opening reaching the first pad electrode and a groove reaching the insulating film are formed. Over the organic insulating film, a plurality of re-wirings each having a barrier metal film and a conductive film are formed. In a plan view, the groove is formed in an area between the re-wirings. At the same time, a width of the groove is smaller than a width of a first portion or a width of a second portion of the re-wirings, respectively, neighboring to each other and extending in a first direction.