Importance: It is critical for providers to use evidence-based interventions to address mental health and behavioral barriers to occupational performance during early childhood.

Objective: To identify evidence-based interventions within the scope of occupational therapy practice to improve mental health and positive behavior for children ages 0–5 yr and their families.

Data Sources: PsycINFO, Cochrane, ERIC, MEDLINE, and OTseeker databases were searched for publications from 2010 through March 2017.

Study Selection and Data Collection: This review was completed in accordance with the Preferred Reporting Items for Systematic Reviews (PRISMA) guidelines. Risk of bias was assessed for each article using either A Measurement Tool to Assess Systematic Reviews (AMSTAR) or the Cochrane method. Articles meeting inclusion criteria were critically appraised.

Findings: Forty-six articles met inclusion criteria and were organized into three themes: touch-based interventions (n = 9), parent–child interaction therapy (PCIT; n = 4), and instruction-based interventions (n = 33). Statistically significant findings and overall risk of bias supported the use of touch-based interventions, PCIT, and parent training.

Conclusions and Relevance: The evidence indicates that touch-based interventions can improve infant self-regulation (strong), social behavior, and attachment (moderate) and reduce maternal stress, anxiety, and depression (low). Moderate-strength evidence supports PCIT to improve child behavior. The evidence indicates that parent training can improve parent behavior, maternal–infant attachment (strong), and parent mental health (moderate). Teacher training can improve mental health and behavior (moderate). Group-based parent training and sleep training have insufficient support (low).

What This Article Adds: Occupational therapy professionals working with children younger than age 5 yr can use the results of this systematic review to guide clinical decision making related to mental health and behavioral outcomes.