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An efficient electrochemical method for the selective oxidation of C-H bonds of unactivated alkanes (BDE ≤97 kcal mol -1 ) and C[double bond, length as m-dash]C bonds of alkenes using a biomimetic iron complex, [(bTAML)Fe III -OH 2 ] - , as the redox mediator in an undivided electrochemical cell with inexpensive carbon and nickel electrodes is reported. The O-atom of water remains the source of O-incorporation in the product formed after oxidation. The products formed upon oxidation of C-H bonds display very high regioselectivity (75 : 1, 3° : 2° for adamantane) and stereo-retention (RC ∼99% for cyclohexane derivatives). The substrate scope includes natural products such as cedryl acetate and ambroxide. For alkenes, epoxides were obtained as the sole product. Mechanistic studies show the involvement of a high-valent oxoiron(v) species, [(bTAML)Fe V (O)] - formed via PCET (overall 2H + /2e - ) from [(bTAML)Fe III -OH 2 ] - in CPE at 0.80 V ( vs. Ag/AgNO 3 ). Moreover, electrokinetic studies for the oxidation of C-H bonds indicate a second-order reaction with the C-H abstraction by oxoiron(v) being the rate-determining step., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)