This textbook explains how to create models with free-form surfaces using CATIA V5. CATIA is a three-dimensional CAD/ CAM/ CAE software developed by Dassault Systems, France. This manual is based on CATIA V5-6R2018. All files are drawn in CATIA V5R18 using later releases of CATIA V5. This manual is suitable for anyone who are interested in learning how to create and use the free-form surface in constructing 3D models using CATIA V5.