Abstract: Since big data is raised to the national strategic level by the united states government in 2012, research and applications of related technologies by domestic and foreign researchers developed rapidly. In this paper, challenges facing C4 ISR systems is first analyzed, as well as the trend of big data and typical big data projects of the american army, then some helpful suggestions are proposed on development of our C4ISR systems in the era of big data by considering big data ecology, key technology and network structure respectively.