The invention relates to the alfalfa variety designated R414M335. Provided by the invention are the seeds, plants and derivatives of the alfalfa variety R414M335. Also provided by the invention are tissue cultures of the alfalfa variety R414M335 and the plants regenerated therefrom. Still further provided by the invention are methods for producing alfalfa plants by crossing the alfalfa variety R414M335 with itself or another alfalfa variety and plants produced by such methods.