PURPOSE: To analyze and compare the tympanometric gradient and the compliance obtained in probe tones of 226 and 1 kHz between groups of infants with and without gastroesophageal reflux (GER). METHODS: Participants were 118 full-term and preterm infants, from newborns to 6-month-olds - 63 with clinical diagnosis of physiological GER performed by pediatricians or gastroenterologists, and 55 without GER -, who were submitted to tympanometry with probe tones of 226 and 1 kHz. RESULTS: Higher compliance values were found with 1 kHz in both groups. Comparing the average compliance between groups, we observed that the group without reflux showed higher values. The mean value of the tympanometric gradient was higher in the group without reflux, when compared to the one with reflux. CONCLUSION: The 1 kHz probe tone has higher compliance in infants with and without GER, when compared to the 226 Hz probe tone. Infants with reflux have compliance within normal limits, although they present lower compliance than infants without reflux. Regarding the gradient, infants with GER have altered values and/or within normality limits in both ears.