The prevalence of Social anxiety disorder (SAD) is believed to be underestimated, although it is a very common condition. The subjects suffering from it often have trouble to search for support. The onset occurs mainly in early adolescence.

The aim of this paper was to evaluate the impact of school and family background on the development of SAD.

Our questionnaire available on a popular social network site, was divided into 4 parts:

1. 1) demographic data (gender, age, site of residence),

2. 2) genetic and organic background (comorbid mental disorders, addictions),

3. 3) situation at school and in the family environment during adolescence,

4. 4) the part designed to define the group that may suffer from SAD with the use of the Mini-Social Phobia Inventory (Mini- SPIN).

226 people were recruited. The age range was 16–61, with the average of 25,8. 71% of the respondents lived in cities with a population of more than 100 000. Male to female ratio was 3:1. According to Mini-SPIN 26,5% of the interviewees might suffer from SAD (28.2% of women and 21.4% of men). Our study showed, that both family and school environment factors have an influence on the development of SAD.

The amount of internet community users that are likely to suffer from SAD, significantly exceeds the clinical data. Both family and school environment factors were shown to be risk factors for the development of this disorder.