This study examined the effect of e-mentoring on vocational identity during teleworking; it clarified the relationship between teleworkers' vocational identity and e-mentoring compared with that of non-teleworkers according to career stage. An online survey was conducted and measured vocational identity and mentoring function (career function and psychosocial function). Collected data from 419 clerical workers (211 teleworkers, 208 non-teleworkers) who had a mentor or a protégé were analyzed. The results of multiple-group structural equation model suggested that in the early career stage, it was especially important for teleworkers to receive psychosocial functions from mentors as protégés. At the late career stage, it was necessary for teleworkers to provide psychosocial functions to protégés as mentors; at that stage, it was important for non-teleworkers to offer career functions. The results also suggested that toward developing vocational identity, the mentoring relationship was more important for teleworkers, who easily become isolated, than for non-teleworkers.