In this study, the effects of inlet air temperature and premixed fuel ratio on RCCI combustion and engine performance characteristics were investigated experimentally. For this purpose, a four cylinder, four stroke, direct injection gasoline engine was operated on RCCI mode with PRF20, PRF40 and PRF60 at 1000 rpm, stoichiometric ratio, inlet air temperature of 40 degrees C, 60 degrees C, 80 degrees C and full load condition. It was seen that maximum in-cylinder pressure and heat release rate increased and advanced with the increase of inlet air temperature and premixed fuel ratio. On the contrary, it was found that combustion was delayed with the increase of premixed fuel ratio at a given inlet air temperature. Indicated thermal efficiency increased by about 7.4 % with PRF60 compared to PRF20 and was obtained 32.3 % at 60 degrees C inlet air temperature. It was determined that PRF60 was the most suitable fuel in view of engine performance. Test results showed that RCCI combustion was sensitively influenced by inlet air temperature and premixed fuel ratio and combustion phasing can be controlled with inlet air temperature and premixed fuel ratio.