The invention is directed towards a method of removing mercury bearing species from a hydrocarbon containing fluid. The method comprises the steps of: i) adding dithiocarbamate polymer to the fluid in an amount such that the number of mercury bonding sites on the polymer exceeds the amount of mercury atoms by at least 10% and ii) removing the mercury bearing dithiocarbamate polymer with a water/oil separation device. The invention relies upon an unexpected reversal in the solubility of dithiocarbamate polymer at very high concentrations. Because of the high solubility the polymer remains within the water phase of the hydrocarbon fluid and can be removed without the need for cumbersome precipitation methods and complicated solid liquid separation devices. As a result, the invention allows mercury contaminated crude oil to be easily rid of its mercury with easy to use equipment already present in a typical oil refinery.