A tandem diolefination reaction of benzaldehyde has been developed via Pd-catalyzed β-C(sp2)-H olefination of the benzene ring and tandem C(sp2)-H olefination of acrylate. 2-((Aminooxy)methyl)benzonitrile was involved with the benzaldehyde substrate as a remote directing group to realize the C-H bond activation. The control experiments proved that the presence of a remote cyano group is essential for this novel diolefination reaction.