Here we describe a web-accessible digital brain atlas of the common marmoset (Callithrix jacchus) at http://marmoset-brain.org:2008. We prepared the histological sections of the marmoset brain using various staining techniques. For virtual microscopy, high-resolution digital images of sections were obtained with Aperio Scanscope. The digital images were then converted to Zoomify files (zoomable multiresolution image files). Thereby, we could provide the multiresolution images of the marmoset brains for fast interactive viewing on the web via the Internet. In addition, we describe an automated method to obtain drawings of Nissl-stained sections.