The present invention provides for a method of decreasing the metals content of metal containing petroleum streams by forming a mixture of the petroleum fraction containing those metals and an aqueous electrolysis medium containing electron transfer agent, and passing an electric current through the mixture or through the pretreated aqueous electrolysis medium at a voltage, sufficient to remove the metals such as Ni, V and Fe from the stream (i.e. to produce a petroleum fraction having decreased content of the metals). The cathodic voltage is from 0 V to -3.0 V vs. SCE. The invention provides a method for enhancing the value of petroleum feeds that traditionally have limited use in refineries due to their metals, e.g., Ni and V content.