Purpose: to investigate the scientific evidence, in the literature, of the relationship between ankyloglossia and breastfeeding difficulties. Methods: an integrative review of the literature. The MEDLINE and PubMed databases were searched, using the following descriptors in combination: "ankyloglossia", "newborn" and "breastfeeding". The searches included articles published between 2014 and 2019, in Portuguese, English and Spanish. Original articles demonstrating an association between ankyloglossia and breastfeeding issues were selected. Results: a total of 31 articles was fully read in the analysis, 22 of which were excluded and 9 included in the review. There was a diversity of instruments used for the diagnosis of ankyloglossia. In four studies, no standardized evaluation instrument was used for the diagnosis of ankyloglossia, which may limit the analysis of the results. However, most studies have evidenced a possible influence of ankyloglossia on breastfeeding. According to the studies, babies with altered lingual frenulum were more likely to experience difficulties in sucking, showing early weaning, which shows the importance of neonatal screening as a routine protocol in maternity hospitals for the cases of ankyloglossia. Conclusions: ankyloglossia may be related to impaired breastfeeding. The standardization of instruments for the diagnosis of ankyloglossia is necessary to improve the evidence in future research.