A new dihydroisocoumarin 3-(2-hydroxypropyl)-8-hydroxyl-3,4-dihydroisocoumarin (1) and a new iridoid 3-deoxyartselaenin C (5), together with six known compounds scopoletin (2), scoparone (3), morindolide (4), pinoresinol (6), medioresinol (7), and secoisolariciresinol (8) were isolated from the stem bark of Chinese mangrove associate Catunaregam spinosa Tirveng. The structures of 1 and 5 were determined by extensive spectroscopic analysis, including 1D and 2D NMR data. All compounds except 2 were obtained from C. spinosa for the first time. And it was also the first time lignans were obtained from Catunaregam sp.