Carbon incorporation in ZnSe films grown by metalorganic chemical vapor deposition is reported. Secondary‐ion mass spectrometry measurements in ZnSe films grown from methylallylselenide and dimethylzinc show an enhanced carbon accumulation at the interface between ZnSe and GaAs. The carbon incorporation in the bulk ZnSe increases with the VI/II ratio and for a value of VI/II=3–4, the amount of incorporated carbon abruptly jumps to concentrations of 1021cm−3, whereupon the films become polycrystalline. A new shallow peakICat 2.7920 eV dominates the near‐band‐edge low‐temperature photoluminescence spectra of all carbon‐contaminated ZnSe films. The intensity and linewidth ofICincrease with the VI/II ratio in a similar manner to the carbon concentration. This peak is proposed to be due to the radiative decay of excitons bound to a complex defect, which is associated with the presence of carbon in the films.