Non-linear optical (NLO) materials possess an importance in laser technology, optical communication and optical storage technology. This review paper deals with the L-histidine family of a single crystal, a promising crystal for non-linear (NLO) applications. The growth of bulk single crystals of these materials has been a subject of permanent disquiet to be useful for device applications. Non-linear optical studies reveal that the dopant increased the efficiency of the L-histidine family of single crystal, and several reports are discussed. Recent papers reveal that the L-histidine family of NLO single crystal possesses excellent optical, thermal, mechanical properties that make it a strong candidate for photonic devices.