A novel molecularly imprinted electrochemical sensor was developed for the sensitive and selective determination of anthocyanins in athletic food products. The sensor was fabricated by incorporating a conductive composite of graphene oxide and gold nanoparticles as the transducer material, which was modified with a silylation agent to enhance compatibility with the molecularly imprinted polymer. The MIP was synthesized using functional monomers that can interact with anthocyanins through hydrogen bonding and π-π interactions. The MIP sensor exhibited a linear response range from 1 nM to 10 μM for cyanidin-3-O-glucoside, with a detection limit of 0.3 nM. The sensor demonstrated high selectivity towards the target anthocyanin, with selectivity coefficients ranging from 7.2 to 48.6 over various interfering compounds. The MIP sensor was successfully applied to the determination of anthocyanin content in commercial athletic food products, with relative errors ranging from -2.1% to 1.3% compared to the reference HPLC method. The recoveries of anthocyanins from spiked food samples ranged from 96.4% to 102.8%.