Protein kinase C (PKC) isoforms are phosphorylated on tyrosine in the response of cells to oxidative stress. The present studies demonstrate that treatment of cells with hydrogen peroxide (H2O2) induces binding of the PKC delta isoform and the c-Abl protein-tyrosine kinase. The results show that c-Abl phosphorylates PKC delta in the H2O2 response. We also show that PKC delta phosphorylates and activates c-Abl in vitro. In cells, induction of c-Abl activity by H2O2 is attenuated by the PKC delta inhibitor, rottlerin, and by overexpression of the regulatory domain of PKC delta. These findings support a functional interaction between PKC delta and c-Abl in the cellular response to oxidative stress.