The sickness insurance has a longstanding tradition in the Czech Lands. The circle of people taking part in sickness insurance scheme has stabilized. The legal regulation of insurance premiums and benefits has been adapting to the economic development in the Czech Republic. In principle, this pay-as-you-go system may be characterized as follows: the sum of collected premiums during a calendar year, i.e. the government budget revenue, is distributed in the form of sickness insurance benefits through the social security administration. Since 2009, payments made to insured employees during the period of their illness have been shared by their respective employers in the form of wage compensation and by the government in the form of sickness insurance benefits. A waiting period is being introduced. The piece analyzes the development of sickness insurance premium and benefits in the period of 1993-2010 in relation to gross domestic product, among others.