Egypt suffers from a huge amount of domestic wastes which causes a lot of economic and environmental problems. This work investigated the possibility of recycling of some of these wastes into green corrosion inhibitors and biocides. The studied aqueous extracts of outer brown peels of onion (A), outer peels of garlic (B), orange (C), and mandarin (D) peels reduced markedly the corrosion rate of carbon steel alloy in 1.0 M HCl and behaved as mixed inhibitors. The inhibition efficiency decreased in the following order: C > B > A > D and generally increased with the increase of the extract concentration. The inhibition mechanism and adsorption isotherms were discussed to describe the adsorption characteristics of the extracts on the carbon steel surface. The extracts of orange and mandarin peels expressed biocidal effect on sulfate reducing bacteria (SRB). However, those of onion and garlic peels did not express any biocidal activity against SRB.