Abstract: Optimization for hydrodenitrification process conditions of coal tar in a fixed-bed hydrogenation unit was investigated using single-factor extraction tests and response surface methodology. The optimized process conditions were found as：reaction temperature of 704.4 K，reaction pressure of 13.48 MPa，hydrogen to oil volume ratio of 1600∶1 and LHSV（liquid hourly space velocity）of 0.20 h－1，under which the nitrogen content of products was 90～100 μg/g. For the high nitrogen mass fraction in coal tar，the hydrodenitrification reaction must be carried out at high temperature，high pressure and low LHSV to get higher denitrification rate. These findings provided some valuable information for further researches in coal tar hydro-upgrading process.