A method for online detecting and analyzing multiple state parameters in fermentation and malodorous pollution processes by using an electronic nose instrument of gas sensitivity and gas chromatography, where the electronic nose instrument includes a gas sensor array module, a capillary gas chromatographic column module, a gas auto-sampling module, a computer control and analysis module and an auxiliary gas source, which is configured to perform cyclically long-term online detection and intelligent analysis of a plurality of bio-fermentation processes or a plurality of malodorous pollution processes.