[Objectives]  To review the nomenclature, and describe the morphological characteristics and larval galleries of Agrilus subrobustus Saunders, a buprestid beetle that frequently causes severe damage to silk trees (Albizia julibrissin Durazz) in order to provide guidance and suggestions for monitoring and preventing damage by this pest. [Methods]  We reviewed the literature to describe the process through which the scientific name of the species was changed, and observed and described the morphological characteristics of adults, pupae, larvae, and eggs inside oviducts. We performed the first geometric index analysis of A. subrobustus’s galleries, including population density, gallery length and width, as well as characteristics of the entrance hole, pupal chamber, and emergence hole. The morphology, and frequency of occurrence and development of complete galleries were analyzed. Based on photographs of galleries and geometric vector indices, proportionally accurate drawings of galleries were made and three dimensional reconstructions completed using Autodesk Maya. [Results]  The larvae of A. subrobustus are ivory colored and slender. Pupae are of the exarate type and adults are shiny and greenish. Features of adult morphology, including the shape (length versus width) of the pronotum, pronotum disk, prehumerus, metasternal projection, elytra pubescence distribution, and aedeagus, are described. The scientific name was clarified through detailed morphological comparisons and consultation of the literature. A. subrobustus damages both the phloem and xylem of A. julibrissin, and is active on the sunny side of host trees. A. subrobustus bores galleries under the bark of its host, with round shaped entrance holes measuring less than 1mm. Pupal chambers were oval shaped and mostly distributed in the xylem of the host with a minority in the phloem. Emergence holes were “D” shaped. Generally galleries could be divided into three types on the basis of morphological characters; i.e. a “Z” shaped, or extended, type, a vertically rounded type, and an ellipse or semicircular, type. [Conclusion]  Clarification of the morphological characteristics and scientific name of A. subrobustus should aid future identification of this beetle. The three dimensional reconstruction of its larval gallery structure will also aid identification and assessment of damage to host trees, and provide technical guidance for the monitoring and control of this pest.