In this work, we design a silicon-on-insulator (SOI) sidewall grating with tunable wavelength, delay, and bandwidth through thermal tuning. Incorporating uniform sidewall corrugations and a linearly chirped rib waveguide, the thermo- optic effect imposed on chirped rib waveguide changes the effective refractive index, due to the resultant of the temperature gradient. Consequently, tunable wavelength, delay, and bandwidth in SOI sidewall grating are achieved. In the numerical simulations, the designed SOI grating is demonstrated with a tunable wavelength from 1 560.7 nm to 1 561.9 nm, a tunable delay from 0 to 38 ps, and a tunable bandwidth from 1 nm to 1.5 nm.