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PURPOSE To report the population-based incidence of pseudostrabismus in the first year of life and the subsequent diagnosis of strabismus. DESIGN Retrospective population-based cohort study. METHODS Setting: A medical record linkage system that captures virtually all medical care provided to residents of Olmsted County, Minnesota. STUDY POPULATION Residents of Olmsted County, Minnesota < 1 year of age diagnosed with pseudostrabismus from January 1, 2005, through December 31, 2014. Main Outcomes and Measures: The prevalence of pseudostrabismus in the study cohort and the subsequent diagnosis of strabismus. RESULTS A total of 184 infants were diagnosed with pseudostrabismus during the 10-year study period, yielding a birth prevalence of one in 113 children in the first year of life. One hundred sixty five (89.7%) were diagnosed by a non-ophthalmology care provider (NOCP) and confirmed by an ophthalmologist, 13 (7.1%) by an ophthalmologist alone, and six (3.3%) by a NOCP alone. Eighty-eight (49.4%) had at least one follow-up visit with ophthalmology, and the median follow-up time from pseudostrabismus diagnosis to the last health care visit that included an eye examination was 7.7 years (interquartile range: 5.8 years). Nine (4.9%) of the 184 infants were subsequently diagnosed with strabismus at a mean age of 4.5 years (range: 1.3 to 8.7 years); seven with esotropia and two with exotropia. CONCLUSIONS Pseudostrabismus is a relatively frequent diagnosis in the first year of life. The prevalence of strabismus among pseudostrabismic infants in this cohort is lower than prior reports and similar to strabismus rates reported in the same population.