The activity at the Institute for Materials Research, Tohoku University on the ab initio phase diagram calculation and the materials database creation has been constantly kept for these 13 years. There, the main aim is to work collaboratiovely with experimental group in the Institute and in other institutions worldwidely to grade up and speed up the output of the reserch works on new materials design and development. The original all-electron full-potential mixed-basis ab initio program (TOMBO=TOhoku Mixed-Basis Orbitals program) has been develped in the group to be used in the numerical computation. To deliver the electronic states, we use TOMBO and other existing ab initio programs fit to the requirement. Cluster variation method, MonteCarlo method, and partition function normalization method are used to estimate the phase stability. Several typical examples of our results on the phase diagram computation will be presented in the talk. Concerning the materials database creation, we are working to establish the non-equilibrium phase diagrams for amorphos metals and artificial magnetic superlattices. The collected information has been treated and part of it has already been published as a series of data handbook from Springer-Verlag; e.g. "Phase Diagrams and Physical Properties of Nonequilibrium Alloys". The contents of and access method to our materials databse will be introduced in the talk.