Abstract. We present a statistical study on the acceleration of CMEs. This study is based on more than 8000 CME events observed by SOHO/ LASCO during January 1996 to December 2009, which observes the inner corona from 1.1 to 30 R_S. In our study we distribute CMEs in three groups- Narrow, Normal and Halo CMEs. Our study shows that narrow CMEs are completely biased towards deceleration and normal and halo CMEs are almost equally distributed towards acceleration and deceleration. Our study shows that correlation between acceleration and speed of CMEs is high for halo CMEs.