The present invention relates to Coix seed oil extracted from Semen Coicis, pharmaceutical preparations thereof, and the use thereof in the treatment of tumors. Specifically, the Coix seed oil contains 5 diglyceride and 11 triglyceride ingredients in the following mass percentages: 1,3-diolein 0.40-0.58%, 1-linolein-3-olein 0.91-1.31%, 1,2-diolein 0.24-0.35%, 1-olein-2-linolein 0.66-0.95%, 1,2-dilinolein 0.33-0.47%, trilinolein 4.87-6.99%, 1-olein-2,3-dilinolein 13.00-18.69%, 1-palmitin-2,3-dilinolein 5.25-7.54%, 1,3-diolein-2-linolein 13.23-19.02%, 1-palmitin-2-linolein-3-olein 10.26-14.75%, 1,3-dipalmitin-2-linolein 2.28-3.28%, triolein 14.44-20.76%, 1-palmitin-2,3-diolein 8.06-11.58%, 1-olein-2-linolein-3-stearin 1.37-1.97%, 1,3-dipalmitin-2-olein 1.52-2.19% and 1,2-diolein-3-stearin 1.29-1.86%.