The thesis relates to friendship. Mainly it is focused on friendship in middle childhood, adolescence, early and middle adulthood, and perception of it. \nIn the first, theoretical part, I summarized some general conclusions about friendship and how friendship between persons is described by other authors. Here I focused on three developmental periods - childhood, adolescence and adulthood. Development takes place in all areas of human life, in my work, social development through human period is very significant. Social development represents an individual’s integration into society and the ability to form relationships with others. Of course, social development is also connected with other areas of development. In short, I presented the history of research relations and important milestones. Friendship is also the differentiation in terms of gender, so I summarized some findings about relationships between genders. \nIn the empirical part, I gained through the questionnaire responses of 150 respondents. Each of the developmental periods mentioned before, consisted of 50 persons. I was wondering, what people think when they hear word »friend« and why it is important to have friends. What are the qualities we search in friends, and whom we trust most – family or friend, and which gender is dominant with friends of men and woman. The data which I gained from questions I analyzed with help of program Excel and I presented them in form of charts and graphs. The results of scale argument I analyzed with a program for statistical analysis SPSS and assessed the importance of the differences between the compared groups participating in different developmental stageswith t-tests. The results obtained here demonstrate that there are differences in the perception of friendship in different developmental stages. Hypothesis that I have set, I confirmed. The results have shown that children tend to choose friends of the same sex, for adolescents and adults gender for friendship is not important. Children have more confidence in their parents, while adolescent in friends. Adults at friends especially appreciate their personal qualities. \n