It is meaningful to develop the scholarly digital archives in a respect that it could preserve the research papers using digital media. The scholarly digital archives provide scientists with the information source with which scientists could actively accomplish research. This study measured based on the citation analysis to what extent PMC, which is life science scholarly digital archives, has an effect on the scholarly communication in the same subject field. The findings are as follows. First, the three citation indicators, impact factor, immediacy index, and half-life, have no remarkable difference in between pre and post-digital archives era. Second, there were more cases that the major citation indicators increased rather than ones decreased with the appearance of the scholarly digital archives, as a result of ranking the scholarly journals after classifying according to subjects.