The paper presents a flexible and simple direct analysis in real-time ( DART) device without grid electrode for mass spectrometer injection. It contained inert carrier gas, ionizer, heater and temperature-controller etc. Excluding the grid electrode and then reducing the structure units, the device could be easy to build up in low cost and flexible to connect with a variety of mass spectrometers. The experimental conditions like the kind of carrier gas, flow rate and temperature were investigated for the device. By using argon as carrier gas, flow rate as 7. 5 L/min, and temperature of heat tape as 300 ℃, the device was used to analyze benzene alcohol, linoleic acid, dichlorvosemulsion, mosquito coils, citrus peel, and sample ( propranolol hydrochloride) on thin-layer plate combined with mass spectrometer. The results were accurate and the device was stable and reliable.