In this study, the numbers, sizes of particles from a single cylinder direct injection spark-ignition (DISI) engine fuelled with gasoline and LPG are examined over a wide range of engine operating conditions. Tests are conducted with various engine loads (2~10bar of IMEP) and fuel injection pressures (60, 90, and 120 bar) at the engine speed of 1,500 rpm. Particles are sampled directly from the exhaust pipe using rotating disk thermodiluter. The size distributions are measured using a scanning mobility particle sizer (SMPS) and the particle number concentrations are measured using a condensation particle counter (CPC). The results show that maximum brake torque (MBT) timing for LPG fuel is less sensitive to engine load and its combustion stability is also better than that for gasoline fuel. The total particle number concentration for LPG was lower by a factor of 100 compared to the results of gasoline emission due to the good vaporization characteristic of LPG. Test result presents that LPG for direct injection spark ignition engine help the particle emission level to reduce.