Continuous transesterification of linseed oil was examined in order to maximize the fatty acid methyl esters (FAMEs) yield. The continuous process was conducted in a packed bed reactor using calcium oxide as a heterogeneous catalyst. In addition, the impact of three variables, namely the molar ratio of diethyl ether (DEE) to methanol, the molar ratio of methanol to oil and the flow rate (ml/min), on the FAMEs yield were studied. The effectiveness of DEE will reveal after comparing transesterification yield in the presence and absence of the co-solvent. The optimum conditions for in continuous method were reported as follows: a molar ratio of DEE to methanol of 1.19:1, a molar ratio of methanol to oil of 9.48:1, a flow rate of 137 ml/min, and temperature of 30 degrees C. Under the optimum conditions, a FAMEs yield of 98.08% was achieved. All the properties such as flash point, pour point, cloud point, and viscosity of the biodiesel from linseed oil were measured by the related specific standards. (C) 2018 Elsevier Ltd. All rights reserved.