In this paper, a summary of works in creating truly three-dimensional structures for high-frequency applications will be presented using an additive manufacturing method, laser-based layer-by-layer polymer stereolithography. This polymer stereolithography is shown to have very good fabrication tolerances, which are necessary for making miniature RF components and narrow-band filters. The prototype components using this stereolithography include high-Q resonators, low-loss cavity filters and evanescent-mode filters, antennas, and miniature ion traps for mass spectrometry.