The aim of the present study was to investigate associations between internalizing and externalizing symptoms and deficits in executive functions (EF) as well as to examine the overall heterogeneity of EFs in a sample of preschool children attending a psychiatric clinic (n = 171). First, based on cut-off points signifying clinical levels of impairment on the parent-completed Child Behavior Checklist (CBCL), children were assigned into groups of internalizing, externalizing, combined or mild symptoms and compared to a reference group (n = 667) with regard to day care teacher ratings of EFs on the Attention and Executive Function Rating Inventory-Preschool (ATTEX-P). Second, latent profile analysis (LPA) was employed to identify distinct subgroups of children representing different EF profiles with unique strengths and weaknesses in EFs. The first set of analyses indicated that all symptom groups had more difficulties in EFs than the reference group did, and the internalizing group had less inhibition-related problems than the other symptom groups did. Using LPA, five EF profiles were identified: average, weak average, attentional problems, inhibitory problems, and overall problems. The EF profiles were significantly associated with gender, maternal education level, and psychiatric symptom type. Overall, the findings suggest that the comparison of means of internalizing and externalizing groups mainly captures the fairly obvious differences in inhibition-related domains among young psychiatric outpatient children, whereas the person-oriented approach, based on individual differences, identifies heterogeneity related to attentional functions, planning, and initiating one's action. The variability in EF difficulties suggests that a comprehensive evaluation of a child's EF profile is important regardless of the type of psychiatric symptoms the child presents with.