The study presented herein aims to identify how recent changes in the world of work occurred in the face of a historical conjuncture of crisis in the capitalism system have affected the conditions of work and labor relations of the social workers in the Southern Region of the State of Rio de Janeiro. A quantitative-qualitative research was conducted by the application of a semi-structured to social works in the region alongside with a letter of invitation as well as a Consent letter. The questionnaire was answered by 101 (one hundred and one) social works in the months of July and August 2015 which allowed us to outline their general profile and to understand and analyze the precarious situation of the working conditions and relations of these professionals. The main results of the research show that the transformation of the world of work in progress since the last decades of the twentieth century have defined precarious work conditions and relationships that directly influence the professional practice of social workers the Southern Region of the State of Rio de Janeiro, such as low pay, increase and diversification of activities that most often are not the responsibility of the Social Services, lack of working space and materials to ensure the professional secrecy to carry out the care of this population, physical problems and psychosomatic diseases, and absence of participation in the bodies of representation and militancy.