Background: Malocclusion is any deviation in the arrangement of teeth exceeding the standards of normal occlusion characterized by anomalies within the dental arches. The objective of this study was to assess the prevalence of malocclusion and its associated factors among pre-school children in Kinondoni and Temeke Districts in Tanzania.

Methods: This cross sectional survey of children aged 3-5 years was conducted in Kinondoni and Temeke Districts in Tanzania. T Parents of pre-schoolchildren were interviewed regarding their socio-demographic details and their child’s sucking habits. Clinical examination was performed to each child to assess malocclusions.

Results: The overall prevalence of malocclusion was 32.5%. In bivariate analysis, sucking habit was the significant factor associated with malocclusions. After controlling for socio-demographic variables, current sucking habits and sex remained significant determinants for having an open bite with odds ratios of 13.5 and 2.2, respectively.

Conclusion: The study showed that more than one third of pre-schoolchildren in the two districts had one or more forms of malocclusions. Open bite was the most common vertical malocclusion trait which was significantly related to sucking habits and child’s sex. Thus, 3-5 year-olds can benefit from preventive and interceptive oral health measures which may either totally prevent or lessen the development of severe forms of malocclusions later in their lives.