Four new ligustilides chuanxiongnolide R1 (1), chuanxiongnolide R2 (2), chuanxiongdiolide R1 (3) and chuanxiongdiolide R2 (4) together with eight known derivatives (5-12) were isolated from the root of Ligusticum chuanxiong Hort. Their structures were elucidated by HR-ESI-MS, UV, IR, 1D and 2D NMR (HSQC, HMBC, (1)H-(1)H COSY, NOESY) methods. The absolute configurations were confirmed via the circular dichroism (CD) spectrum. The anti-inflammatory assay in LPS-triggered RAW 264.7 macrophages was carried out on the twelve compounds. 1, 3, 5 and 6 showed significant inhibitory effects against LPS-induced NO production.