In this study, we interviewed clients who received EAP counseling service and identified the factors that can measure the outcomes of EAP counseling service by grounded theory approach. And EAP scale were developed to measure the identified factors. In Study 1, structured interviews were conducted for seven subjects and analyzed the results according to the grounded theory analysis method. The data saturation appeared in the data analysis of the 7th interviewee. According to the results of grounded theory analysis, the outcome factors of EAP counseling of work welfare net are self understanding, self - esteem, information provision, new persfective, role overload, interpersonal relationship at work, management ability, career management, emotional stability, depression symptoms, somatization symptoms, and family relations. In Study 2, preliminary questions of 7 items were made for each 13 factors. After the consultation of two specialists of counseling professors, the items were revised to final 91 question pools and 400 adult workers were surveyed along with the questions and the existing similar scales. As a result of the factor analysis, it was confirmed that the items were classified according to the factor structure originally assumed. The correlations between each sub - factor and the existing similar scale showed that there was a significant correlation and it was confirmed that the scale had acceptable level of convergence validity. Finally, the internal consistency of each sub - factor was verified as .806 ~ .903. The significance and limitations of the above results are discussed.