The feasibility of mid-to-high-rise timber buildings was examined and proven from the following 2 aspects:1. A hybrid structural system using CLT walls and steel frames, that can utilize the high strength and stiffness of CLT, was proposed, and full-scale steel frame-CLT wall test showed high performance.2. Practical structural analysis model was developed and validated by full-scale steel frame-CLT wall test, and it was found that the strength and stiffness could be evaluated with high accuracy.