The results of more than 10 large scale international studies allow assessing the quality of education in mathematics, science, reading, civic education and informatics in the primary, basic and secondary schools of Latvia in the international comparison. The repeated cycles of the above mentioned studies indicate a stable increase in the quality of education of Latvia during the last decade (OECD SSNP 2003, IEA TIMSS 1999, TIMSS 2003, PIRLS). The increase in the achievement of the 15 year old Latvian students in the OECD PISA study is one of the highest among the countries participating in the first two cycles (2000 - 2003) [1]. The key attention in the presentation is devoted to the national secondary analysis of the PISA 2003 data, mainly in the aspect of the Riga (the capital) and other urban and rural schools of Latvia with the aim of comparing the possible differences in the achievement of the students of these groups and of finding the factors determining them. The aim of such an analysis is based also on the differences stated in the previous studies which serve as an evidence for the unequal possibilities of acquiring equally qualitative education in the schools of Riga, other towns and rural areas. As regards the rural students then the principle of social equity on the possibilities of acquiring qualitative education is violated to a certain extent. The results are obtained by using the correlation calculations and the analysis of the indices and other derived measures from the student and school context questionnaires in the context of students in Riga, other urban and rural schools. More than 10 international comparative studies during the last 13 years show that the best mean achievement in the international tests in Latvia is scored by the students of Riga schools followed by students of town schools and finally, the rural schools [2,3]. The mentioned phenomenon is rather general because it is found in all studies in a relatively long period of time in all stages of education and in all subjects and their groups in which there have been the studies.The analysis of the recent data of PISA 2003 shows that there is a positive correlation between; " the achievement of the 15 year old students of Latvia in the international tests with several factors characterizing students' families (parents' education and profession, employment, learning resources, number of books at home, etc.); " the students' desire to obtain higher education in future" the use of computer at home, the skills of working with the Internet, etc.However, the values of almost all the above mentioned as well as other indices from the student context questionnaires differ in Riga, other towns and in the country thus these factors determine higher achievement namely for students in Riga.The rural students have more limited possibilities of choosing the school, 69% of them learn in the school of their vicinity (in Riga there are 38% of such students). PISA 2003 data also provide evidence for several more positive aspects mainly in the rural schools if compared with the Riga and other urban schools" There are better student- teacher mutual relations; " There is a greater teacher support for the students in mathematics lessons; " There is a larger relative number of students who have additional classes or more intensive lessons in mathematics. The positive changes in the education system of Latvia ensure the increase in the quality of education, including the more rapid increase in students' achievement mainly in the country schools. It is necessary so that the positive processes become irreversible and the improvement of the education system continues.References1. Organisation for Economic Co-operation and Development. 2004. Learning for Tomorrow's World - First Results from PISA 2003. Paris: OECD, pp. 370. 2. Geske Andrejs, Kangro Andris. 2004. Different achievement of urban and rural students in Latvia in the context of international comparative studies. Humanities and Social Sciences. Latvia. 2(42)/2004 Riga: University of Latvia, pp.22-38. 3. Geske Andrejs, Grinfelds Andris, Kangro Andris , Kiselova Rita. 2004. Macišanas nakotnei. Latvija OECD valstu starptautiskaja skolenu novertešanas programma 1998 - 2004. (Learning for Tomorrow`s World. Latvia`s results in OECD PISA 1998-2004), Riga: Latvijas Universitates Akademiskais apgads, 118.lpp. (in Latvian)