Micro stereolithography and two-photon lithography based on photopolymerization have been widely used for making complex 3D models ranging from several hundred centimeters to micrometers as high-resolution 3D printing techniques. In particular, two-photon lithography can produce 3D microstructures with submicron resolution beyond the diffraction limit of light. In three decades, various kinds of photocurable materials such as polymers, nanocomposites and hydrogels have been developed and used to create functional 3D microdevices including micro optical components, microactuators, microfluidic devices, metamaerials, bio-scaffolds and so on. Functionalization of 3D-printed polymer microstructures is also realized by the combination of post processes such as electroless plating, chemical and thermal treatments. In addition, 3D molding, using 3D printed master models, can replicate complex 3D microstructures made of polymers and ceramics. The 3D molding techniques are useful for mass production of 3D micro components. Furthermore, several types of multi-material stereolithography and two-photon lithography have recently been demonstrated, and highly functional 3D microstructures that combine multiple materials with different properties such as color, refractive index, and mechanical strength can be made directly without any assembly process. Threfore, multi-material 3D micro/nano printing are useful for further miniaturization and integration of microdevices. In this presentation, I will talk about brief history and overview of micro stereolithography and two-photon lithography, and introduce our recent activities on microscale 3D printing.