In modern economic societies, individuals are governed by organizations and they managed their daily lives in one way or another. through such organizations. All activities of the organizations are carried out by the job performance of individuals. Job is a very important factor for both individuals and organizations. The study is the explore. the effect of job characteristics and organizational characteristics on the job satisfaction in the small- and medium- sized firms in Namdong und Banwool Area. Job characteristics and organizational justice were hypothesized to be positively related to job satisfaction. To examine the influence of job characteristics and organizational justice on job satisfactions, data were collected from 320 employees of the small- and medium- sized manufacturing companies in Namdong und Banwool Area. This research took independent variables as the core job characteristics of the job characteristic theory such as skill variety, job stagnation, job importance, autonomy, feed back, and organizational justice as distributive and procedural justice. As a result, I can make the following suggestions. First, The Results show that job characteristics and organizational justice were significant and important predictors of job satisfaction. Secondarily, to raise the job desire of organizational members, job must be designed in such a way that the members can highly recognize their job characteristics.