The method for producing a superheavy oil emulsion fuel includes the steps of (a) adding to a superheavy oil 0.1 to 0.6 parts by weight of a nonionic surfactant having an HLB (hydrophilic-lipophilic balance) of 13 to 19, based on 100 parts by weight of the superheavy oil, and water, to prepare a homogeneous liquid mixture; and (b) mechanically mixing the homogeneous liquid mixture with a high shearing stress, to produce a superheavy oil emulsion fuel having a particle size distribution. In this method, a 10% cumulative particle size is from 1.5 to 8 .mu.m, a 50% cumulative particle size is from 11 to 30 .mu.m, and a 90% cumulative particle size is from 25 to 150 .mu.m, and coarse particles having particle sizes of 150 .mu.m or more occupy 3% by weight or less in the entire emulsion fuel, and the concentration of the superheavy oil is from 76.5 to 82.0% by weight.