Background: Delayed verbal communication and vocabulary development can significantly impact children's emotional well-being, social interactions, and overall psychological development. This systematic review aims to synthesize existing research on the psychological effects associated with these delays, focusing on how they affect children's emotional health, social skills, and cognitive functioning. Methodology: This review systematically analyzed studies that investigated the psychological consequences of delayed verbal communication and vocabulary development in children. The studies included were diverse in design, including cross-sectional, longitudinal, and mixed-method approaches. Key measures across studies included assessments of depressive and anxiety symptoms, social-emotional functioning, language skills, and cognitive abilities. The analysis synthesized findings from a range of populations, including children with developmental language disorders (DLD), specific language impairment (SLI), and autistic spectrum disorders (ASD). Results: The review found that children with delayed verbal communication and vocabulary development are at increased risk for a variety of psychological issues. These include higher levels of anxiety and depression, difficulties in social interactions, and cognitive challenges. Specifically, children with DLD and SLI were more likely to experience emotional difficulties, such as depressive symptoms and anxiety, compared to their peers. Pragmatic language difficulties were found to be particularly associated with later psychotic experiences and depressive symptoms. Peer problems, bullying, and socioemotional challenges were prominent among youth with language impairments. Additionally, deficits in higher-order language skills and cognitive abilities were linked to greater emotional and social difficulties. Conclusion: The psychological impacts of delayed verbal communication and vocabulary development are profound, affecting children's emotional well-being, social interactions, and cognitive development. Interventions should address both language difficulties and associated emotional and social challenges.