Abstract A passive‐matrix monolithic full‐color InGaN light emitting diode (LED) microdisplay with 40 × 40 full‐color pixels is demonstrated. Each full‐color pixel consists of red, green, and blue (RGB) subpixels that have a pitch size of 40 μm × 120 μm. The full‐color microdisplay is monolithically fabricated on blue/green dual‐wavelength LED epilayers, using red quantum dot photoresist as a color converter. Pure RGB emission and a wide color gamut are achieved, as shown by electroluminescence spectra. Full‐color patterns with controllable grayscale and color mixing can be clearly rendered driven by a full‐color microdisplay controller, indicating tremendous potential of this novel approach for full‐color LED microdisplays in the future.