Objective: to evaluate the influence of behavioral states on the readiness of the premature infant to initiate breastfeeding. Methods: the study was transversal, observational and descriptive with 51 premature infants, attended at the Neonatal Intensive Care Unit (NICU), from a Baby-Friendly Hospital. The infants were evaluated using the «Preterm Oral Feeding Readiness Assessment Scale». The evaluation occurred close to the feeding time and was performed in preterm infants in two behavioral states, in deep sleep and alertness. Thus, preterm infants were self-controlled. For the data analysis, the T-Test and the McNemar Test were applied, with a significance level of 0.05. Results: there was a statistically significant difference in the behavior of premature infants in alert behavior and deep sleep. In the alert state, preterm infants showed greater readiness for oral feeding in the breast. The results highlight the importance of the behavioral state of prematurity for professionals working in NICUs. Conclusion: the behavioral state influences the beginning of premature infant feeding. The alertness behavioral status of premature infants is essential during neonatal speech therapy assistence.