The scale of journal publication in the fields of science, technology and medicine (STM) in Japan has been determined from a merged title list of bibliographic databases and electronic journal sites. In 2005 there were 2,655 scholarly journals in active publication along with a similar number of university bulletins and several hundred university periodicals. The journals were mostly published by academic societies, which is clearly different from the situation in Europe and the USA. Among these journals, 964 titles were online on either J-STAGE, NII-ELS, Medical Online, or American/European publisher sites. The degree of digitization was high for English-language journals (80.3%), but much lower for Japanese-language journals (29.6%). Journal coverage by major bibliographic databases was also analyzed. The English-language journals were fairly well indexed (67.8%) by at least one of the four main databases, MEDLINE, SCI, CA, or Scopus.