In this work, 3D flower-like MoS2 microspheres with nanosheets were synthesized by a simple thiourea-assisted hydrothermal route and employed to support gold nanoparticles in order to fabricate a novel nitrite sensor. By this method, stable and well-distributed gold nanoparticles were formed due to the electrostatic attraction between APTES-functionalized MoS2 and citric-stabilized gold nanoparticles. Electrochemical investigations indicated that Au NPs/MoS2 nanocomposites exhibited an excellent performance towards nitrite oxidation. Under the optimal experimental condition (pH 6.0), the sensor displayed a wide linear range from 5.0 mu M to 27.8 mM with a high sensitivity of 117.0 mu AmM-1 cm(-2) and a low detection limit of 1.67 mu M. In a word, the present study demonstrates that the Au NPs/MoS2 composites are promising electroactive materials for developing nitrite sensors with great potential.