In June 2003, Japanese two universities, University of Tokyo and Tokyo Institute of Technology successfully launched the world first CubeSats "XI-IV" and "CUTE-1" using Russian rocket together with 4 other universities' CubeSat. That was the icebreaking event as to micro/nano/pico-satellite development activities in Japan and the world. Triggered by the success of XI-IV and CUTE-1, many universities in Japan started their own satellite projects, mostly for educational objectives, and 37 Japanese university satellites have been launched till now. University of Tokyo already developed 8 satellites, and 7 of them were launched and operated successfully in orbit. Two CubeSat "XI-IV(2003)" and "XI-V (2005)" were primarily for space engineering education, but from the third satellite "PRISM" we have been challenging towards more practical applications. PRISM aims to obtain about 30 m resolution Earth remote sensing images, which was actually achieved in 2009. Our fourth satellite "Nano-JASMINE," which is now waiting for launch, has "Astrometry" mission to obtain very precise 3D map of large number of stars in space. From 2010, I organized nationwide micro-satellite project named "Hodoyoshi Project," through which, three Earth remote sensing satellites "Hodoyoshi-1,3,4" were launched in 2014 by Russian Dnepr, which showed excellent performance of taking Earth pictures of 6m, 40m and 240m ground resolutions, with which we are now seeking practical applications for agriculture, forestry, fishery, disaster monitoring, etc. Based on the bus technologies developed in Hodoyoshi Project, in December 2014, we launched world first 50kg- class deep space probe "PROCYON," which escaped from Earth gravitational field and various observation and experiment were conducted successfully in deep space. Based on the obtained technologies, we just started development of 6U CubeSat "EQUULEUS" targeting towards Earth Lunar Lagrange Point 2 to be launched by NASA's SLS rocket in 2018. In this way, University of Tokyo has been stepping up from education to practical applications of micro/nano/ pico-satellites, and plans to extend their applications to wider areas. In my talk, I will show this history, some technical details and discuss future possibilities of micro/nano/pico-satellites.