Language not only plays a powerful role in human life, as it is also a crucial factor in our minds. It shapes our personality, memory and even the way in which we see the world, as well as playing a fundamental role in the building of self-concept and self-esteem. Having a good self-concept, that is, knowing one’s own qualities and strengths, will, in turn, promote good self-esteem. The aim of this research was to analyze self-concept in 50 children (aged 5–7) with functional dyslalia in the city of Granada (Spain). A quantitative approach was taken, with a non-experimental design; it was descriptive, cross-sectional and correlational. The Perception of Child Self-concept Scale (PCS), a Spanish scale, was used. In general, the children who were interviewed showed a medium level of self-concept. It is noteworthy that differences were found in the average scores on the scale according to the sex of the children, with girls showing a higher level of self-concept than boys. Participants scored higher on Factor 1, family attachment, followed by Factor 3, feelings, with the values of both these factors decreasing with age. On the other hand, lower average scores were found for Factor 2, environment, and Factor 4, autonomy. It was found that self-concept was higher in young children (five-year-old children) as well as in those who studied in rural areas. Finally, guidelines for improvement were provided. Self-concept is a fundamental aspect of personality, but it is not innate; it develops and evolves.