The importance of sperm DNA damage in infertility is known. In addition, sperm maturation defects have been shown to be one of the DNA damage mechanisms and their level is determinant in IUI pregnancies. Especially in varicocele cases, the negative effects of rising testicular temperature are known. Therefore, in our study, we aimed to investigate the effect of temperature used in sperm incubation and also the effects of two sperm selection methods on sperm DNA integrity and chromatin maturation. This prospective controlled study was conducted in the normospermia (n:40), oligoastenoteratospermia (n:40) groups that applied to Biruni University Hospital between JanuaryJune 2018 for semen analysis. Male patients between the ages of 27-45 were included in the study and patients without a diagnosis of endocrinological and / or metabolic disorder and varicocele and / or urinary tract infection were selected. In normospermic and oligoasthenoteratospermic (OAT) cases, swim-up and density gradient methods were used for sperm selection. After sperm selection, samples were kept at 22 and 37 °C, sperm DNA fragmentation was assessed with acridine orange stain, sperm maturation was assessed by acidic aniline blue test. In both selection methods, sperm motility increased and DNA fragmentation decreased. Especially in cases of OAT, the negative effects of incubation at 37 °C in terms of DNA fragmentation appeared compared to normospermia. In our study, it was found successful in selecting sperms with DNA damage and maturation defect by both gradient and swimup method in normospermia or OAT cases (p <0.05). In both sperm selection methods, a temperature of 37 °C was observed to cause an increase in sperm DNA fragmentation (p <0.05). There was no difference in results in terms of sperm maturation. In IVF laboratories, incubation temperature is generally 37 °C in sperm preparation. It has been understood that the use of room temperature in long-term incubations may reduce sperm DNA damage due to its damaging effects. The study should be evaluated with IVF results.