Numerous biotic and abiotic factors can affect foraging success and diet composition of fish larvae, potentially leading to changes in growth and survival. Bighead Hypophthalmichthys nobilis and Silver Carp H. molitrix (collectively bigheaded carp) are planktivorous fishes invasive to the United States that alter plankton communities in invaded areas and have caused declining populations of native fishes. Consequently, bigheaded carp may compete with larval native fishes due to diet overlap, but no study has assessed in‐situ changes in larval native fish diets. We investigated larval Freshwater Drum Aplodinotus grunniens foraging success, diet composition, and the abundances of various prey taxa in larval diets across a gradient of bigheaded carp relative abundance and in relation to zooplankton density, temperature, discharge, and larval fish densities in the Upper Mississippi River (UMR). We sampled fish larvae and zooplankton every 10 days (May‐August, 2017 and 2018) from UMR Pools 14, 16, and 18‐20, collected environmental data from nearby gaging stations, and assessed bigheaded carp relative abundance. Crustacean zooplankton abundance was positively related to larval foraging success. Copepods were the dominant prey, but larvae also consumed large proportions of rotifer eggs and benthic insect larvae. Bigheaded carp presence and CPUE were positively associated with increased consumption of atypical prey (rotifer eggs and insect larvae) and cyclopoid copepods. Cladocerans were the rarest prey consumed where bigheaded carp were present but were more frequently consumed where bigheaded carp were absent. In addition to bigheaded carp abundance, river discharge was negatively associated with the consumption of cladocerans, insect larvae, and rotifers, water temperature was negatively associated with the consumption of copepods and cladocerans, and rotifers abundance was positively associated with their consumption. We suggest bigheaded carp alter larval fish diets to prey that may be less energetically beneficial and can have implications for larval growth and survival.