The aim of the study is to evaluate the impact of selected social and environmental factors on girls’ puberty. The study was conducted on the group of 3855 girls residing in lubuskie voivodeship, aged 10–16. The material was collected in 2015–2016 by the employees of the University of Zielona Gora The diagnostic survey was used in the study as a research method. As a research tool a questionnaire containing retrospective questions was applied. The collected material was analyzed statistically calculating the arithmetic means of the studied traits, standard deviation, minimum-maximum, coefficient of variation and the level of significance of differences. The detailed analysis of the material shows that on average the girls who mature early are those:– who live in small and medium towns in relation to the girls living in rural areas with a statistically significant difference; – whose fathers have higher education with a statistically significant difference in relation to the daughters of fathers with the lowest education;– whose mothers have higher education;– whose fathers and mothers are white-collar workers;– who were first-born children with a statistically significant difference in relation to girls born as third or subsequent children;– who are only children; only children matured the earliest and a statistically significant difference was observed between them and the girls from large families. Residential environment, father’s education, birth order and number of children in the family proved to be powerful factors that are statistically significant determinants of girls’ early puberty. Over the last 15 years, the age of menarche has lowered, which proves that environmental conditions (especially nutrition and hygiene) of our society has improved significantly.