MXenes have recently been used to grow highly textured potassium niobate ferroelectric crystals. Herein, the versatility of MXenes is further demonstrated by growing ferroelectric and luminescent lithium niobate (LiNbO3) crystals from niobium carbide MXene (Nb2CTx). The formation of high-aspect-ratio LiNbO3 rhombic crystals is confirmed by extensive structural analysis. The ferroelectricity of MXene-derived LiNbO3 is verified, using standard ferroelectric and dielectric measurements. In addition, for the first time, Pr3+-doped LiNbO3 crystals are synthesized with simultaneous visible photoluminescence (PL) from Nb2CTx MXene. This work demonstrates that it is possible, by using the 2D character of MXenes, to fabricate high aspect ratio and well-oriented photoluminescent ferroelectric crystals for advanced optoelectronic applications.