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In this paper, we demonstrated the fabrication and measurement of sidewall gratings integrated in a hybrid type of optical waveguide: As2S3-Ti:LiNbO3. This hybrid waveguide is constructed by patterning arsenic tri-sulfide (As2S3) strips on the midline of titanium-diffused channel waveguide in lithium niobate (Ti:LiNbO3). Sidewall gratings are written on both sidewalls of As2S3 strips by electron beam lithography (EBL) with 3% PMMA resist and a dose 350 μC/cm 2 at 50-kV electrons. The measured reflectance bandwidth was between 2.4 and 6.7 nm. Coupling coefficients ranging from 2.5 to 8.9 mm-1 were obtained. A transmission peak with a 3-dB bandwidth of ~0.25 nm was observed in the rejection band of a 432 μm-long phase-shifted sidewall grating. Such sidewall gratings integrated in hybrid As2S3-Ti:LiNbO3 waveguide can be used for numerous integrated optical devices including optical filters, switches, modulators, lasers, sensors, and wavelength division multiplexing (WDM).