The purpose of this translation of Collado's Ars Grammaticae Iaponicae Linguae of 1632 is to make more readily available to the scholarly community an annotated version of this significant document in the history of both Japanese language study and grammatical description in general. Collado's work, derived in all its significant features from the Arte da lingoa de Iapam completed in 1608 by João Rodriguez, is in a strict, scholarly sense less valuable than its precursor. However, if used with the Arte as a simplified restatement of the basic structure of the language, Collado's Grammar offers to the student of the Japanese language an invaluable ancillary tool for the study of the colloquial language of the early 17th Century. While less extensive and less carefully edited than the Arte, Collado's Grammar has much to recommend it as a document in the history of grammatical description. It is an orthodox description attempting to fit simple Japanese sentences into the framework established for Latin by the great Spanish humanist Antonio Lebrija. Thus, as an application of pre-Cartecian grammatical theory to the structure of a non-Indo-European language, the Ars Grammaticae is an important document worthy of careful examination by those wishing insight into the origins of what three centuries later was to become the purview of descriptive linguistics. The present translation was begun with the able assistance of Ms. Roberta Galli whose contribution to my understanding of the Latin text is most gratefully acknowledged. For his continued encouragement in this undertaking I am grateful to Professor Roy Andrew Miller. Thanks are also due to the Graduate School of the University of Kansas for its support in the preparation of the manuscript and to Ms. Sue Schumock whose capable typing turned a scribbled, multi-lingual draft into a legible manuscript. The imperfections are my own.