Head-attached interface device (HIDE) has been developed as a new type of human interface device in an actual work envi-ronment. The HIDE has flexible integrated functions which consist of speech recognition and view direction detection as hand-free input channels, direct presentation of audio/visual information as output channels, and mobile system configura-tion. In this paper, the design concept of the HIDE was first introduced, and individual functions to configure the design concept were developed by their separate testing. An inte-grated prototype system HIDE was then produced, and its functional evaluation test was made to examine the individual functions. According to the evaluation result, we proposed a design guideline of application software, and developed an example software.