Abstract: A device for simulating nicotine release from oral smokeless tobacco product in human mouth was developed,which consisted of a container for solvent,a constant flow pump,a constant temperature trough,a pre-heating coil,a thermostatic tube,a thermostatic cell,and a liquid collector.The thermostatic cell acted as a buccal cavity to ensure nicotine to be released in the cell under a constant temperature of 37℃.The device was convenient in operation and good in stability and could effectively simulate nicotine release behavior of oral smokeless tobacco products and distinguish the difference of nicotine release between different products.The novel technique is suitable for quality evaluation,and nicotine level control of oral smokeless tobacco products as well as the assessment of bioavailability of nicotine.