Mud volcanism consists in the surface extrusion of gases, saline waters and mud breccias, which produce conical edifices of various sizes with morphology similar to that of magmatic volcanoes. In this work, DInSAR technique has been used to investigate the ground deformation related to the activity of Azerbaijan mud volcanoes during the period October 2003-November 2005. This work focuses on two important deformation events at the Ayaz-Akhtarma and Khara-Zira mud volcanoes. The ground deformations at mud volcanoes are generally originated by fluid pressure and volume variations in the reservoir. The observed deformation pattern is characterized by pre-eruptive inflation that reaches a cumulative value of up to 20 cm at Ayaz-Akhtarma in about two years. Similar pre-eruptive bulging has been observed at magmatic volcanoes, where uplift is typically associated with magma intrusion. We conclude that mud and magmatic volcanoes display some similarities in the behavior of ground deformation during pre-eruptive stages.