OBJECTIVES: Analysis of utilization of the right to sick leaves of the beneficiaries of the Republic Health Insurance Institute(RHII) in the period from January to September 2005, lasting more that 30 days, analysis of the reasons for sick leaves and suggested measures for more efficient control over the rights to benefits, upgrading of utilization and guaranteeing the rights, providing equal rights to all beneficiaries,and abuse reduction. METHODS: Statistic data processing by uniform statistic forms containing data on all medical commissions, classification of groups of deseases according to the ICD-10. RESULTS: The total number of beneficiaries with temporary work disability was 263,825, 50,316 were enabled, 213,509 were given extensions and 28,387 beneficiaries were sent to DMC. The most common reasons for sick leaves were: vascular deseases 12.73%, bones, joints & muscles system 11.36%, mental and behaviour disorders 10.85%, injuries – distorsions and fractures 9.05%, tumors 6.13%, pregnancy 5.57% and nervous system diseases 3.45%. These groups of deseases are, by importance, the main cause of absence from work in all the regions. The rate of sick leaves over 30 days for the entire territory of the Republic of Serbia is 7.06%. The point of interest here is that this rate is very uneven in varous regions and amounts from 1.72% to 18.27%. The total liabilities of RHII in the period from January to September 2005, for reimbursement of sick leaves were EUR 56,732,175. CONCLUSIONS: Data obtained by this analysis illustrate that the sick leave rate is very high and uneven, which is the result of absence of medical doctrine standards for evaluation of temporary work disability. In addition, the most frequent reasons for sick leaves are the effects of bad habits, poverty and risk factors: smoking, lack of physical activity, overweight and generally poor life quality and insufficient protection at work by employers.