Recent microtechnology has opened various application fields in chemistry. In analytical chemistry, in particular, ‘Micro Total Analysis Systems (μ-TAS)’, has been established as one of the largest research fields. On the other hand, growing interest has also focused on applications in biochemistry and synthetic organic chemistry. In this paper, we introduce some applications for Continuous-Flow Chemical Processing (CFCP), immunoassay, and organic synthesis by using a surface modification as examples of micro chemical processes.