SND detector operates at the VEPP-2000 collider (BINP, Novosibirsk). To improve events selection for physical analysis and facilitate online detector control we developed new data quality monitoring (DQM) system. The system includes online and reprocess control modules, automatic decision making scripts, interactive (web based) and program (python) access to various quality estimates. This access is implemented with node.js server with data in RDBMS MySQL. We describe here general system logics, its components and some implementation details.