The purpose of this study is to suggest the directions for building national digital archiving strategies. This present paper begins with surveying S&T information resources especially in public sector, and analyse the priority criteria for appraising and selecting the resources for long-term preservation. Emphasis is placed on identifying the critical tasks for each type of resources including scientific data, technical reports, theses, journal, web, e-prints, etc. and some levels of organizations in the national digital archiving framework. Based on the analysis, it suggests some strategic agenda for developing national digital archiving system.