Background: The ability to understand the mental state of others (social cognition), as well as language, is crucial for children to have good social adaptation. Social cognition (SC) has been shown to be a hierarchical model of three factors (Cognitive, intermediate and affective SC) interrelated with linguistic processes. Children on the autism spectrum and children with developmental language disorder (DLD) or social communication disorder (SCD) manifest language and SC difficulties, albeit in different ways. Aims: This systematic review aims to find how language and SC interact with each other and identify linguistic and socio-affective profiles in the target population. Methods: About 1593 articles were systematically reviewed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guide in November 2022, obtaining, through inclusion/exclusion criteria, a total of 38 articles for qualitative assessment. The majority of them were on autism (26) or DLD (14) and to a lesser extent SCD (3). Main Contribution: Although SC is related to all components of language, SC is strongly related to narrative and morphosyntax and partially related to lexicon. Pragmatics shows a complex relation with SC due to greater sensitivity to other factors such as age or task, and prosody appears to be more related to emotional processes. Besides, autistic, SCD and DLD children showed differences in their language and socio-affective performance. Mainstream DLD children have lower performance in general language, where autistic and SCD children have more linguistic variation and are lower in pragmatic and SC tasks, SCD children being more associated with language production difficulties and autistic children with both receptive and productive language. Conclusion: Each language component has a different interaction with SC. Likewise, different linguistic profiles are partially found for each disorder. These results are important for future lines of research focusing on specific components of interaction and socio-emotional processes, as well as for clinical and educational treatment.