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To design functional materials based on composite materials, it is imperative for us to understand the mechanism of adhesion between different materials such as metal and polymer. In this study, we investigated the adhesion between NiCr alloy film with three different compositions Ni100, Ni90Cr10, Ni60Cr40 and polyimide film using surface forces apparatus combined with optical microscope, which enable the observation of contact area during the measurement of the adhesion. This composite is widely used in the electronic devices as substrates, wiring, etc. The adhesion force measured in air for Ni90Cr10 and Ni60Cr40 decreased by time while that for Ni100 remained constant. In the measurement under nitrogen gas atmosphere, the order of strength became Ni60Cr40 Ni90Cr10 Ni100, and the decrement in adhesion for Ni90Cr10 and Ni60Cr40 was reduced. These results indicated that the Cr has stronger interaction with polyimide compared to Ni, and enhance the adhesion with polyimide. This was also supported by the larger hysteresis in the contact area vs normal load for Ni60Cr40 and Ni90Cr10 surfaces. However, Cr can be oxidized easily by exposure to air, which resulted in the decrease in the adhesion.