The formation of HCN and NH3 from fuel nitrogen during pyrolysis was studied in a prefilled reactor system with slow (temperature-programmed) heating and in a drop-in reactor system with a rapid heating rate. The experimental results indicate that the formation of HCN and NH3 is obviously affected by coal properties. The effects of these coal properties vary with the heating fashion. Coal rank, characteristic of char residue, surface characteristics, and composition of the coal are important factors influencing the formation of HCN and NH3 during pyrolysis.