For some tourism destinations, climate represents a natural resource on which the tourism industry is predicated. Data covering the period from 1949 to 2012 for two meteorological stations, Sombor and Zrenjanin was used to compute the Physiologically Equivalent Temperature (PET) and Tourism Climate Index (TCI) for two special nature reserves in Vojvodina, North Serbia, “Gornje Podunavlje” near Sombor and “Carska bara” near Zrenjanin. Information on thermal comfort/stress conditions as well as aesthetical and physical parameters is considered. Before calculation of PET and TCI, homogeneity test was applied for the detection of possible abrupt changes in the climate records. The monthly PET values were produced using the RayMan Model. The distribution of comfortable condition with no thermal stress occurred in April, May, September and October, with 3.2%, 76.2%, 60.3% and 6.3% respectively for Sombor meteorological station. For Zrenjanin meteorological station distribution of comfortable condition with no thermal stress occurred in April, May, June, September and October, with 14.0%, 70.7%, 7.8% 59.3%, 3.1% respectively. The investigated sites have a summer peak distribution of TCI with maximum values ranging from 85 to 98. The frequency distribution of mean monthly climatological parameters for the period from 1950 until 2012 for Special nature reserves “Gornje Podunavlje” (meteorological station Sombor) and “Carska bara” (meteorological station Zrenjanin) was used to assess the climate conditions. Additionaly Climate Tourism Information Sheme CTIS is a used for a graphical description of analysed tourism-related parameters and frequency classes on monthly time scale.