An electro-conjugate fluid (ECF) is a kind of functional fluid, which produces a flow (ECF flow) when subjected to a high DC voltage. This study develops a novel inchworm robot having flexible body and using two suckers both of which are driven by the ECF flow. The robot imitates the movement pattern of inchworm and is introduced the ECF to realize the motion. First, we developed and evaluated an ECF flow generator, a pressure source integrated sucker and an expansion/contraction actuator (flexible body). Next, we developed a prototype with 59 mm long, 12 mm wide and 9.5 g weight. Finally, we conducted moving experiments of the robot on an acrylic board. The robot could move on a horizontal surface, and on surfaces with inclination of 5° and 10°.