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Applications of thin films have been widely increased especially in microelectronics industry. In order to advance the development of thin film technology, measuring mechanical properties properly becomes important for the reliability of electronic devices because the difference of mechanical properties arises in small scale [1]. Existing tensile test methods have difficulties of making and handling free-standing specimens. In this paper, a novel methodology for thin films tensile testing by floating on water surface is presented. This method is capable of investigating intrinsic material properties of thin films floating on the water surface due to negligible adhesion of metal thin films with water surface which makes water surface very suitable to be used as underlying substrate for thin films tensile test. A dog-bone-shaped specimen which is E beam evaporated gold has been tested as a model material due to its inert nature and increasing demand in electronic devices. This method consists of fabricating gold thin films floating on water surface, attaching PDMS coated grips with the thin film specimen and applying tensile load through movement of linear DC motor. Accurate real time strain monitoring is ensured by digital image correlating (DIC) set up device as shown in Fig. 1. The validation of this proposed tensile method has been examined by first testing 500 nm gold films at a constant strain rate and then comparing the results with other studies [2-4]. After validating this methodology, 50 nm thin gold films were tested to study specimen thickness effects on mechanical behavior and apply for much thinner specimens. This new method can provide the direct way to measure the mechanical properties which is closer to its intrinsic properties with the convenient of handling the thin film specimens.