© 2021 Kare Publishing. All rights reserved.Objectives: This study aimed to explain sleep habits of infants and investigate the factors that may affect their sleep in the first 3 months after birth. Methods: Infants who were born between October 29, 2014, and November 30, 2014, at the Department of Gynecology and Obstetrics were recruited for this study. A face-to-face interview was conducted to mothers of the infants within the 3 days after birth. The mothers were asked to fill out the "Baby sleep evaluation questionnaire" and the Edinburgh Postnatal Depression and Beck Anxiety Scale were filled. All questionnaire were applied monthly. Results: The study included 70 infants. The mean sleep duration of 1-month-old infants was found to be 14.0 }2.4 hours, while the mean daily sleep duration of 3-month-old infants was 13.7 }2.0 hours. While 10 (83.3%) of the mothers who experienced anxiety in the second month stated that their babies had poor sleep quality, 23 (39.7%) of the mothers who did not have anxiety evaluated the sleep quality of their babies as poor (p=0.010). When comparing the first, second and third months of the babies separately, factors such as using a pacifier, nasal obstruction, nurse availability, or sex had no effect on sleep duration and waking frequency (p>0.05). Conclusion: Poor sleep quality reported by mothers decreases toward the third month. It was evaluated that the babies of mothers with anxiety in the second month had worse sleep quality than babies of mothers without anxiety.