Sheikh Abdinasir Haji Ahmed recently arrived in Jubbaland state to attend a religious gathering.
According to eyewitnesses the bomb was planted in his car.
Sheikh Abdinasir Haji Ahmed was a well-known Somali cleric based in Las Anod city, Sool region.
In the past week alone, Somalia has been the scene of over a dozen deadly terror attacks by al-Shabab. The Islamist militant group is seen to be bent on thwarting the forthcoming elections in the Horn of Africa country.