Chen, Y., Shen, X. and Fang, Y. 2013. Fenclorim effects on rice germination and yield. Can. J. Plant Sci. 93: 237-241. Weedy rice (Oryza sativa f. spontanea) is a serious problem in rice-producing areas. The objective of this study was to evaluate the effect of the safener fenclorim on rice seed germination and yield when used in conjunction with the pre-emergent herbicide pretilachlor in the growth chamber and in the field. Rice seed germination was accelerated by soaking seeds in fenclorim (0.67 g L-1), and pretilachlor (0, 450, 900, 1800, 3600 and 7200 g a.i. ha-1) was applied 1, 3, 6, 12, 24, and 48 h after sowing in a growth chamber. Seeds were also soaked in fenclorim, and then pretilachlor was sprayed (0, 450 and 900 g a.i. ha-1) 1 h after sowing in the field. The percentage of seedling germination for cultured rice was significantly increased by soaking in fenclorim prior to application of the pre-emergence herbicide pretilachlor compared with the control in the growth chamber. The application of the safener fenclorim increased rice yield by 56% and 50% in treatments with 450 and 900 g a.i. hm-2 pre-emergence pretilachlor, respectively, and the weed population, height, and dry matter production were significantly reduced by pretilachlor application.