The work analyses the business activities of the Slovak Bank (Slovenska banka) in Bratislava. This bank built up its business organization, numerically the largest in the Slovak financial sector, after 1918. The main emphasis is on the business activities of the 'Slovenska banka' in joint stock companies concerned with industry, trade, transport and finance from the founding euphoria of 1919-1921 through the bankruptcy of some companies during the post-war economic crisis to the consolidation in the boom years of 1926-1929. The 'Slovenska banka' built up its business organization mainly in the years 1919-1921 with substantial help from the 'Zivnostenska banka' (Trade Bank) of Prague. It also gained shareholdings in the various companies on the basis of fusion with the 'Hospodarska banka' (Business Bank) of Bratislava. In 1922, 45 companies were included in the sphere of influence of the 'Slovenska banka'. However, their number and capital value were reduced by the economic crisis. From 1924 to 1929, the 'Slovenska banka' devoted its efforts mainly to the recovery of it's the most important companies.