An exhaust emission control apparatus for diesel engines is offered which is capable of achieving better power performance and exhaust emission purification efficiency in an optimally reconciled manner, and from which torque deficiency during hill climbing on a steep slope is eliminated. Emulsified fuel including light oil, water and emulsifier supplied respectively from a light oil tank 4, a water tank 5 and an emulsifier cartridge 6, of which the water ratio is adjusted by flow variable control valves 11-13, is supplied to a combustion chamber 4. The water ratio is normally set to a basic water ratio corresponding to the signal of an accelerator opening sensor 39 (Step S32). However, when a difference between target acceleration and actual acceleration of a vehicle corresponding to the accelerator pedal opening exceeds a predetermined value (Step S36), the basic water ratio is corrected so as to reduce the water ratio (Step S37).