Most school-aged children are at risk to experience behavioural or emotional difficulties. Children Mental Health Research data reveal that 14% of 7-10-year-olds are diagnosed with mental health disorder. Traditionally, school focuses on children’s performance results. However, mental health is a significant factor that increases the number of dropouts and determines poor performance results or behavioural problems in different environments. Various researchers agree that these behavioural problems fall into two categories – internal and external ones. Internalizing behaviour problems include social withdrawal, demand for attention, feelings of worthlessness or inferiority, and dependency. Externalizing behaviour problems comprise difficulties with interpersonal relationships and rule breaking as well as cases of irritability and belligerence. Children with high or above average intellectual abilities are thought to be very adaptive and resistant to behavioural and emotional difficulties because of their higher abilities. However, there are researchers who oppose by saying that because of the higher abilities, gifted children are sensitive to interpersonal conflicts, feel more stress and have more behavioural problems. There is a lot of research carried out with gifted adolescents, however, the first behavioural symptoms can be noticed in primary school-age children and, thus, successfully be reduced. The aim of this article is to analyze internal and external difficulties of primary school-age girls and boys with high and above average intellectual abilities. 155 gifted primary school-age children, identified by Ravens’ Coloured Progressive Matrices, participated in this research. Their parents and teachers filled in Goodman’s Strengths and Difficulties Questionnaire. Statistic data analysis was carried out to compare internal and external difficulties of moderately and highly gifted children with those of the general population and between gifted girls and boys. The findings of this study are as follows: a smaller percentage of gifted children who demonstrate behavioural and emotional difficulties fall into the deflection category in comparison to the general population. All gifted boys demonstrate bigger external problems than girls. A deeper analysis shows that gifted boys collect more scores in Behavioural problem and hyperactivity scale in comparison to girls. However, analysis of internal difficulties revealed an unexpected tendency: although, in the general population, girls experience more internal problems than boys, in our sample no difference between boys and girls was observed. This research also confirmed that there are certain differences between teachers’ and parents’ ratings. It proves that it is of key importance to use information from different sources when identifying and evaluating gifted children. Thus, we can minimize the possibility of overlooking any difficulties and not providing the necessary help to satisfy the needs of such children. Keywords: primary school age, high and above average intellectual abilities, boys and girls, internal and external difficulties. How to cite: Girdzijauskienė, S., & Kardelytė, K. (2015). Aukstų ir aukstesnių nei vidutinių intelektinių gebėjimų pradinio mokyklinio amžiaus vaikų internalių ir eksternalių sunkumų ypatumai [Internal and external difficulties of primary school-age children with high and above average intellectual abilities]. Ugdymo psichologija, 26 , 57–74.DOI: http://dx.doi.org/10.15823/up.2015.05