We report for the first time the results of tensile stress testing of thin film conductive structures patterned by stencil lithography on a PI substrate. The goal of this investigation is to determine the effects that mechanical deformation occurring in real applications can have on electrical parameters of metal interconnects in flexible electronic circuits. The thickness of thin film gold conductors is of the order of 10 nm, while their lateral dimensions are in the micrometer range. Electrical parameters of thin film conductors are measured under uniaxial tensile stress and in the relaxed state after subjecting them to a number of stretching and relaxation cycles. SEM imaging of the test structures was used for observing of possible changes in thin film surface morphology caused by the applied tensile stress.