1-Butyl-3-methylimidazolium hydrogen sulfate ([Bmim][HSO4]) is utilized to catalyze transesterification of camelina oil with methanol. The major compositions of camelina biodiesel are saturated fatty acid esters (C16:0, C18:0), monounsaturated, and polyunsaturated fatty acid esters (C18:2, C18:3). The effects of reaction temperature, reaction time, M-methanol:M-Camelina oil, and M-[Bmim][HSO4]:M-Camelina oil on biodiesel production are investigated in detail, and a general mathematical model is developed to well predict the biodiesel yield. Also, [Bmim][HSO4] is thermally stable to recycle for four times with a high biodiesel yield. The fuel properties of camelina biodiesel are all comparable to the American Society for Testing Materials (ASTM) standards.