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Planet host stars with well-constrained ages provide a rare window to thetime domain of planet formation and evolution. The NASA K2 mission has enabledthe discovery of the vast majority of known planets transiting stars inclusters, providing a valuable sample of planets with known ages and radii. Wepresent the discovery of two planets transiting K2-264, an M2 dwarf in theintermediate age (600-800 Myr) Praesepe open cluster (also known as the BeehiveCluster, M44, or NGC 2632), which was observed by K2 during Campaign 16. Theplanets have orbital periods of 5.8 and 19.7 days, and radii of $2.2 \pm 0.2 $and $2.7 \pm 0.2$ $R_\oplus$, respectively, and their equilibrium temperaturesare $496 \pm 10$ and $331 \pm 7$ $K$, making this a system of two warmsub-Neptunes. When placed in the context of known planets orbiting field starsof similar mass to K2-264, these planets do not appear to have significantlyinflated radii, as has previously been noted for some cluster planets. As thesecond known system of multiple planets transiting a star in a cluster, K2-264should be valuable for testing theories of photoevaporation in systems ofmultiple planets. Follow-up observations with current near-infrared (NIR)spectrographs could yield planet mass measurements, which would provideinformation about the mean densities and compositions of small planets soonafter photoevaporation is expected to have finished. Follow-up NIR transitobservations using Spitzer or large ground-based telescopes could yieldimproved radius estimates, further enhancing the characterization of theseinteresting planets.

K2-264: A transiting multi-planet system in the Praesepe open cluster