The　quality　of　the　microfluidic　chip　will　influence　the　separations,　injections,　reactions　and　measurements　of　samples　in　the　microfluidic　system,　it　is　essential　to　detect　the　structure　such　as　the　width,　depth　and　roughness　for　evaluating　its　performance.　Aiming　at　this　requirement,　digital　holography　microscope　method　is　developed　to　achieve　the　quantitative,　non-contact　phase　imaging　with　the　full　field.　Firstly,　the　digital　image　plane　holographic　microscopy　is　designed,　and　the　complex　amplitude　of　the　whole　wave　field　is　reconstructed　by　the　angular　spectrum　method.　The　two-step　phase　subtraction　and　surface　fitting　methods　are　combined　to　eliminate　the　phase　aberration,　and　the　unwrapped　phase　information　is　extracted　using　the　least-squares　phase-unwrapping　algorithm.　Meanwhile,　we　acquire　the　profile　parameters　of　the　microchannel　using　white　light　interferometer,　and　the　results　demonstrate　that　the　digital　image　plane　holographic　microscopy　is　feasible　and　effective　for　the　profile　measurement　of　microchannels　in　the　microfluidic　chip.