This paper aims to present the only Armenian manuscript of the Library of the Royal Canonary of Premonstratensians at Strahov (Czech Republic). It is being studied for the first time (Bibliotheca regiae canoniae Strahov-Pragae, Num 536, Sign D.C.V.8.). It is the so called Stephanyan’s Gramatice (author is Stephanos Stephanyan Roshka), which is rewritten in 1726 in Stanislavov by scribe Martiros Senienc. The Stephanyan’s Gramatice is a variation of Gramatice of the Armenian language. This is the fifth known manuscript of the Stephanyan’s Gramatice all over the world.