The termination of lease contracts of residential and roofed business premises has been regulated under the 347th article of Turkish Code of Obligations numbered 6098. First paragraph of the article regulates the termination of lease contracts for residences (dwelling houses) and roofed business premises (working places) concluded for a limited duration (fixed term contracts). Pursuant to the first paragraph of Article 347, at the fixed term lease contract of residential and roofed business premises, the contract is deemed to be extended for one year under the same conditions unless the tenant gives notice at least fifteen days prior to the expiration of the contract. The lessor cannot terminate the contract based on the expiry of the contract period. However, at the end of the ten-year extension period, the lessor may terminate the contract without any justification grounds, by giving at least three months' notice before the end of each extension period. It is controversial when the ten-year extension period will begin and when the lessor can use the right to terminate at the earliest. In addition, in cases where the lease term is agreed for a period of more than ten years, when the lessor can use the right of termination, is a matter to be evaluated separately. In this study, in terms of the termination of fixed term lease contracts for residential and roofed business premises, the issue of the beginning of the ten-year extension period and the earliest time that the lessor can notify the end of the contract for termination is evaluated in the context of opinions and judicial practice. Finally, our opinion regarding the subject as de lege lata and de lege ferenda is explained.