Abstract: A method and apparatus for testing tack of Pressure Sensitive Adhesives (PSA) and other sticky materials is disclosed to simplify the measurement of bonding and debonding procedures. A modified rolling tack test is applied using a device attached on to an Instron Universal Testing machine. By predetermining the angle (position) of a cylindrical probe-roller hanging down to the Instron's cross-head and leaning parallel to a rotary drum covered with tacky substance, the pressure of the probe and its rolling velocity (as an expression for dwell time) can be controlled independently. The ease of execution and its high reproducibility enable the use of the new method to study the experimental tack of adhesive materials.