The article presents the Polish educational system, its constituent part - upper secondary education, in particular. Describing the qualitative changes in the upper secondary schools (secondary schools of the second extent) the author singles out one significant document that has changed the direction of education, created the conditions for change of the educational management system and introduced the economic rules in educational activities. It also shows the structure of upper secondary education, which was formed in the final stage of the educational reforms. The peculiarities of the qualitative changes have been indicated. The previous system of assessing students' knowledge was preserved; however, an external evaluation of the students' achievements was introduced. The introduction of the external exams and assessments has enabled a fair comparison of the level of skills that the student has achieved to the skills that are required by the syllabus. Therefore, it is believed that the changes introduced have become one of the pillars of the reform of the educational system in Poland. The quantitative changes have been introduced along with the qualitative ones. Quantitative changes were compared in the period 2000-2015 and juxtaposed with the year 1990. On the basis of the gathered statistical data a trend was set (downward or upward) in Polish upper secondary education.