Objectives: The literature suggests that there is a relationship between motor function and cognitive development however, few studies have explored the specific role of Functional Movement Skills on cognitive function. This research aimed to determine if Functional Movement Skills predict cognitive function, when accounting for confounding factors, in a sample of primary school children in Ireland. Design: Cross-sectional. Methods: Sixty primary school children (51.7 % girls, age range 7–12 years, mean age 9.9 ± 1.28) were assessed in their Functional Movement Skill proficiency using the Test of Gross Motor Development—3rd Edition and a subtest of the Bruininks–Oseretsky Test of Motor Proficiency 2 Short Form (to assess balance). Participants also completed a series of cognitive tests which formed part of the Cambridge Neuropsychological Test Automated Battery. Results: A series of hierarchical regression analyses were conducted whilst controlling for covariates (Age; Gender; Socio Economic Status). Attention Switching, Reaction Time, and Emotional Recognition were found to be associated with Overall Functional Movement Skills (Locomotor, Object Control, Stability). Overall Functional Movement Skills significantly accounted for 4.7 % of the variance in Simple Reaction Time (ΔR2 = 0.032; p = 0.13) whilst Stability significantly accounted for 5.5 % (ΔR2 = 0.055; p = 0.04) and 12.9 % (ΔR2 = 0.129; p = 0.00) of the variance in Simple Reaction Time and Emotional Recognition, respectively, after controlling for covariates. Conclusions: Overall Functional Movement Skills may be more related to reaction time than attention and spatial working memory, whilst stability may be more associated with emotional recognition. Further research is warranted. Greater comprehension of the impact of Functional Movement Skills on cognitive function in children can contribute to the development of more effective and efficient physical activity programmes, which can in turn contribute to and promote holistic child development