An GaAs-based micro-opto-electro-mechanical system (MOEMS) cantilever tunable light emitting diode was presented. It is fabricated by standard surface micromachining technology. The relation of cantilever loading and displacement was measured, and the tunable spectrum of this cantilever tunable light emitting diode was also measured. When the current is 40 mA and applied voltage is from 4 V to 22 V, the wavelength is tuned from 974.5 nm to 956.9 nm and a wide tuning range of 17.6 nm was achieved under the room temperature. The optical and mechanical characters of the cantilever with distributed Bragg reflector (DBR) multiple layers in detail were studied by the finite element method. Further numerical simulations with MOEMS-cantilever show when the length of cantilever is 400 μm, the max-displacement of center of cantilever is 411 nm, and max-voltage is 24 V.