This Master’s thesis focuses on calculation of power and temperature distribution in fuel assemblies of VVER-440 reactor at Dukovany Nuclear Power Plant. Theoretical section contains a brief description of VVER-440 technology, fuel and its development at Dukovany Nuclear Power Plant, basics of heat generation in nuclear reactors as well as an overview and categorization of computer codes, used for core calculations. Of these codes, the MOBY-DICK computer code is then described in depth, including its input and output files. The MOBY-DICK code is later on used for pinwise calculating power distribution of selected fuel cycles of defined units at Dukovany Nuclear Power Plant, with vizualization of output values for characteristic fuel assemblies. Results of this computation are then used for analysis, whether uneven power distribution in the core and heat generation gradient within fuel assemblies have any influence on measuring channel output temperatures, which is the pivotal part of this thesis.