Aims: The aim of this study was to describe the nutritive and non-nutritive oral sucking habits (breastfeeding, bottle use, pacifier/dummy/soother use, thumb/finger sucking) of preschoolers with and without phonological impairment, and to determine whether oral sucking habits are associated with the presence and severity of phonological impairment. Methods: We conducted a cross-sectional study of 199 Australian English-speaking preschoolers with and without phonological impairment. Preschoolers’ speech was directly assessed, and parents/caregivers completed a questionnaire. Chi-square (χ2) tests were used to examine relationships between oral sucking habits and the presence and severity of phonological impairment. Results: Based on caregiver reports, 79.9% of participants had been breastfed (33.3% for >12 months), 58.3% had used a pacifier (74.2% for ≥12 months), 83.9% had used a bottle (73.4% for > 12 months), and 15.1% sucked their thumb/fingers. There was no association between a history of oral sucking and the presence and severity of phonological impairment. Conclusion: The majority of preschoolers had been breastfed and bottle-fed, and more than half had used a pacifier. The findings support an understanding that phonological impairment is not associated with a history of nutritive and non-nutritive sucking habits. Research is needed to examine the association between oral sucking habits and other types of speech sound disorders.