Surface plasmon resonance (SPR)-based DNA biosensors have been shown to be rapid, label-free, and selective tools for the detection of PCR products. Here, we describe an SPR sensor based on DNA hybridization for the detection of Fusarium culmorum , a fungal pathogen of wheat. A 0.57 kb DNA fragment of F. culmorum was amplified by specific primers, and a 25-mer oligonucleotide probe was selected within the sequence of the PCR amplicon. The biotin-labeled probe was immobilized on a streptavidin sensor chip and tested for biospecific interaction with PCR products of F. culmorum . The SPR biosensor was applied to the detection of F. culmorum in fungal cultures and in naturally infected wheat samples.