A study to identify the influence of vocational education on an individual's underemployment analyzed data from a Taiwan labor use survey conducted in May 1993. Data were restricted to 9,415 respondents who were currently employed, aged 20-65, and not in the army; who had participated in general or vocational high school education; and for whom all data were complete. Findings indicated the following: males found full-time employment more easily; male vocational business high school participants were less likely to be underemployed than male general high school participants; younger people were less likely to be underemployed than those above age 40; and married women had a higher probability of being underemployed than single women, whereas married men had a higher probability of becoming fully employed than single men. Living in a region with a high unemployment rate made female and general high school participants more likely to become underemployed. Women or general high school participants who lived in a municipality were more likely to be fully employed than their reference groups who lived in rural areas. The probability of being underemployed was higher for workers in the service sector than those in the industry sector. The probability of being fully employed was higher for workers in a large company. Men or general high school participants who had changed jobs in the last year had a higher probability of becoming underemployed. (Appendixes include 11 references and 5 data tables.) (YLB)