The thesis attempts to provide an analysis of the role of trade union membership in the formations of trade union consciousness and worker identity and the assumption that the trade union membership is influential in the formation of worker identity is tested in this study. It is mainly based upon a field study conducted in Railcar Factory of T&Uuml / VASAS in Sakarya, makes a comparison between union member workers and non-union member subcontractors in terms of the formation of trade union consciousness and worker identity. It will also be possible to point out concretely that the formations of trade consciousness and worker identity are analysed through perceptions, consciousness and attitudes by taking the social, economic and political dimensions into consideration. It is analysed that the trade union membership has not a significant influence on the formation of worker identity and there are no big differences among the union member workers and subcontractors in terms of the aproaches towards trade unionism, working class consciousness and worker identity.