The title compound, C(8)H(9)NS, has four symmetry-independent molecules in the asymmetric unit. These molecules link into two independent infinite N-H...S hydrogen-bonded chains in the a-axis direction with graph-set notation C(2)(2)(8). The NH-CS group adopts a trans conformation and forms a dihedral angle of about 50 degrees with the phenyl ring. The intermolecular hydrogen-bond energy calculated by the density functional theory (DFT) method is -14.95 kJ mol(-1). The correlation between the IR spectrum of this compound and the hydrogen-bond energy is also discussed. This molecular system is of interest because of its biological function.