The aim of this study was to analyze the needs of job-related in-service training for vocational training instructors. The research also analyzed the needs of special training in digital new-technology areas related to the 4th industrial revolution to enable more effective in-service training for vocational training instructors. The scope of this study was as follows: (1) 361 NCS sub-classifications in which the number of actively working vocational training instructors during the last three years (2017-2019) are above 60, (2) 13 digital new-technology areas. In addition, an online survey was administered to 2,794 vocational training instructors. To analyze the needs of job-related in-service training, three ways of methods were used including the paired sample t-test, the formula for the priority decision of Borich, and the Locus for Focus Model. This study found that 169 NCS sub-classifications and 7 digital new-technology areas had higher needs on job-related in-service training for vocational training instructors. The results of the study can be used as useful data when developing needs-based job-related in-service training and establishing the standards for in-service training for vocational training instructors.