Nowadays improvement of productivity along with investment in IT is the most important goal of organizations. But at same time productivity statistics shown no improvement but rather a slow growth and that is itself has caused a paradox, namely "IT productivity paradox". This paradox has led the experts to question the productivity of IT seriously. The main purpose of this study is to examine the relationship between IT investment increase and growth of productivity in organizations. Also providing a model for IT productivity improvement and identigy complementary of organizational activities regarding IT are of later concern in this study. The main hypothesis in this study is, "introducing IT into an organization will change the applied technology in that organization (with accordance to Leavitt and Scott model). And if we consider organizations as an open system the effectiveness of IT investment require changes on organizational variables such as personnel, goals/duties and structure simultaneously". In this study the above variables are named IT complementarities. The statistical population is Housing and Urban Development Organizations of Provinces and samples are chosen in an accidental fashion. Survey data are obtained from questionnaire and productivity figures are collected from related organizational documents. Statistical test applied in this study are: one way variance analysis also Spearman's correlation coefficient is applied for hypotheses testing and Freedman test is used for IT complementarities ranking.The finding of this study shows that measured productivity in organizations that invested on IT and simultaneously on organizational complementarities of IT such as IT Business alignment, reengineering of process, restructuring, human resource training, delegation of authorities, establishing free flow of information and integrated information systems was higher compared with other organizations.