As　for　the　issue　of　the　rapid　wavelength　interrogation　of　optical　fiber　wavelength-encoded　sensor,　a　demodulation　method　combining　spectrum-to-time　domain　information　mapping　and　photonics　time　stretch　technology　is　proposed.　Using　group　velocity　dispersion　effect　of　dispersive　elements,　the　spectrum　of　optical　pulse　will　be　mapped　to　a　temporal　waveform　whose　intensity　mimics　the　spectrum.　The　temporal　waveform　is　further　stretched　in　timescale　so　that　it　is　slow　enough　to　be　captured　by　electronic　analog-to-digital　converter.　The　performance　of　the　proposed　demodulation　method　is　experimentally　demonstrated　to　demodulate　a　wavelength-encoded　sensor.　(C)　2018　Society　of　Photo-Optical　Instrumentation　Engineers　(SPIE)