This book has been prepared by benefiting from the notes used by the author in his commercial law courses in English given at different faculties and different universities since 2015. In the book, the author preferred to examine the basic concepts of Turkish Commercial Law with a user-friendly approach. The aim is to conclude a book that can be used by both students and professionals who want to learn about Turkish commercial law. Introduction to commercial law, commercial enterprise law, which can also be expressed as business law, company law and lastly negotiable instruments law are included in the book as the main branches of commercial law. In order to reinforce, in the book, sample questions and at the same time more than 200 slides were also presented to the users.