Development Psychologists are people who studies cognitive, psychological and social development of human beings. In their studies, Development Psychologists focus both on biological influences and environmental aspects- factors that shapes an individual. The salary of development psychologists varies from one state to another in the United States. A development psychologist can make as much as $84,487 per year in New York-Manhattan while in Houston, Texas, the average salary is $70,393. A development psychologist can earn $85,087 on an average in Chicago.