This experimental study uses Electrical Capacitance Tomography (ECT) technique for measuring the void fraction in two phase bubble flow regime. Void fraction was measured by using differential pressure calculations in a vertical fluid column (ECT sensor) with inner diameter 4.93 cm and height 40.996 cm. The online ECT sensor also measures the raw capacitance and voltages of the flow by varying the flow rates of deionized water and air. In this way different flow regimes were established in the test rig which is further modeled and analysed by using MS Excel / MATLAB. The proposed study is to measure the void fraction in a bubble flow regime of a twophase flow using differential pressure (�p) and ECT. © 2010 IEEE.