Aluminum Titanium Nitride films deposited by thermal CVD method (CVD-AlTiN) has attracted cutting tools suppliers because of their high potential for milling of alloy steel and cast iron. One of the most interesting characteristics of CVD-AlTiN films is the amount of Al. It is higher than that of AlTiN films deposited by PVD method. It is well-known that conventional AlTiN films deposited by PVD method has cubic structure in the range of Al content lower than about 0.7, while they obtain hexagonal structure in the range of Al content higher than 0.7. However, CVD-AlTiN films can keep cubic structure in Al content higher than 0.7, which prevents their cutting properties from getting worse.We also focused on the unique and promising properties of CVD-AlTiN and realized practical use as cutting tools. In this report, we would like to summarize the development of CVD-AlTiN films with high Al content.