Two new quinolin-2(1H)-ones, 7-methoxy-6-methyl-4-(4-methylfuran-2-yl)quinolin-2(1H)-one (1) and 7-hydroxy-6-methyl-4-(4-methylfuran-2-yl)quinolin-2(1H)-one (2), were isolated from the twigs of Cassia auriculata. Their structures were determined by means of HR-ESI-MS and extensive 1D and 2D NMR spectroscopic studies. Compounds 1 and 2 were tested for their anti-tobacco mosaic virus (anti-TMV) activity. The results showed that compounds 1 and 2 exhibited potential anti-TMV activity with inhibition rates of 38.4 and 49.2%, respectively. [ABSTRACT FROM AUTHOR]