This study applied Data Envelopment Analysis (DEA), a multiple inputs-multiple outputs evaluation tool, to analyse the comparative performances of six high-tech industries currently developed in Taiwan. These six high-tech industries are semiconductor, computer, communications, photo-electronics, precision equipment, and biotech. The results indicate that computer and semiconductor industries have the best performance. Communications, photo-electronics, and precision equipment industries perform at the middle level, while the biotech operates at a worst level. Communications and photo-electronics industries have a satisfying average scale efficiency score, but a poor pure technical efficiency score. On the contrary, the biotech industry reveals a lowest average scale efficiency score, but a highest pure technical efficiency score among the six. A slack analysis was used to analyze the gaps between the optimal and current inputs and outputs to achieve an improvement direction for each sector.