Jacques Mering (3 January 1904–29 March 1973) was a Lithuanian-born, naturalised French engineer, well known in the fields of clay mineralogy and clay science, in graphite studies, and in the applications of X-ray diffraction and electron-optical methods to these.
Mering earned a Diplôme d'Ingénieur en Génie Electrique (Engineering Degree in Electrical Engineering) from École Spéciale des Travaux Publics in Paris in 1925, and Licencié de Sciences (BSc) from Faculté des sciences in Paris in 1928. He rose to become director of research at the Centre National de Recherche Scientifique (CNRS; France's National Centre for Scientific Research) in Paris; subsequently, in 1969, Mering founded and, until his death, directed the CNRS Centre de Recherche sur les Solides à Organization Cristalline Imparfaite (Research Center on Solids with Imperfect Crystalline Organization), in Orléans, France. Mering is also remembered for his formative influence on the British physical chemist Rosalind Franklin, whom he trained in X-ray crystallography in Paris, and who, until her untimely death, produced DNA crystallographic data of exquisite quality.