In this work, calculations of the design of bremsstrahlung photon collimator within the scope of the Turkish Accelerator Center Project are presented. At TARLA facility (Turkish Accelerator Radiation Laboratory at Ankara), bremsstrahlung photons created by the accelerated electron beams, are transferred to the experimental area through the collimator, which has a conical geometry with length of 320 cm. In this study, Al, Fe and Cu materials were selected as collimator materials. All interactions between the collimator materials and Gaussian photon beam in 8-32 MeV energy range (8 MeV, 16 MeV, 24 MeV and 32 MeV) were taken into account. The entry radius, geometry and chosen materials are important parameters for collimator design. The photon fluence from collimator, secondary particle distributions and the number of photons, scattered from the collimator, were calculated as functions of these parameters. All calculations were made with the Monte Carlo code FLUKA. According to the results of these simulations, collimator with conical geometry, made of aluminium, with 0.25 cm entry radius, was determined to be appropriate for TARLA bremsstarhlung photon facility of Turkish Accelerator Center.