In this work, a binary metal sulfide composite (CoS2-MoS2) was obtained by a hydrothermal method. To further improve the electrochemical activity of CoS2-MoS2, an activated N-doped lignocellulose was composited with CoS2-MoS2. The resulting composite was denoted as N-LC/CoS2-MoS2, which was modified onto glassy carbon electrode (GCE) and used as a simple and non-enzymatic electrochemical biosensor. Nyquist plots of electrochemical impedance spectra showed that the N-LC/CoS2-MoS2 modified GCE had better electrocatalytic activity than bare, MoS2 and CoS2-MoS2 modified GCE. Cyclic Voltammetry (CV) results displayed the N-LC/CoS2-MoS2 had excellent electrocatalytic activity toward ascorbic acid (AA), dopamine (DA) and nitrite. The amperometric response results indicated the N-LC/CoS2-MoS2 modified GCE could be used to determine AA, DA and nitrite concentration in wide linear ranges of 9.9-6582, 0.99-261.7 and 0.5-5160 mu M, respectively. And the sensitivities of the N-LC/CoS2-MoS2 modified GCE for AA (516-6582 mu M), DA and nitrite (179-5160 mu M) are 4941.8, 73.3 and 5732.9 pA mu M-1 cm(-2), respectively. The corresponding detection limits were 3.0, 0.25 and 0.20 mu M, respectively. The proposed sensors had good anti-interference properties and stabilities.