A　novel　three-dimensional　profilometric　measurement　system　based　on　a　computer　aided　image　processing　technique　is　presented.　This　system　consists　of　a　single　mode　optical　fiber　coupler　with　phase　shifting　as　the　grating　projector.　A　piezoelectric　(PZT)　cylinder　wrapped　by　one　arm　of　the　optical　fiber　coupler　is　utilized　to　introduce　phase　shift.　Satisfactory　results　have　been　obtained　in　the　practical　measurement　with　this　measuring　system.　This　system,　owing　to　the　advantages　of　quite　simple　optical　configuration,　extremely　small　size　and　light　weight,　high　visibility　and　sinusoidal　intensity　distribution,　would　find　high　practical　value　in　applications.