Abstract: Development of a maritime space surveillance system require from state authorities to make a reasonable choice of sources of information. The subject of this research is the surveillance system structure that allows to observe sea vessels. Providing that there is a great number of approaches to control over sea vessels that are based on both complex information systems and individual technical means, when selecting sources of information it is necessary to take into account functions that are to be performed by systems or means to observe and control over sea vessels. In particular, to select sources of information it is necessary to consider the performance of control functions by surveillance system elements. The research methodology is based on theoretical and empirical methods, in particular, structured fnctional approach, methods of analysis, synthesis, induction, comparison, literature analysis and performance analysis. In this research the author offers his own method of ranking information sources for maritime space surveillance. The method offered by the author has certain benefits compared to existing ones, in particular, the method allows to take into account not only technical parameters of information sources but also efficiency of control over maritime space of the Russian Federation. The method also allows to compare information sources with different structures and principles of operation as well as heterogenous incomparable technical features. The method also enables to consider the state of a surveillance system being used in which a ranked information source may be imbedded.