The electronic transport properties of a single quintuple bond [PhCrCrPh] molecule sandwiched between two Au(111) surfaces with the trans-bent and linear configurations are studied by a fully self-consistent nonequilibrium Green's function method combined with density functional theory. The calculated transmission spectra of two chemical isomers are remarkably distinctive. Theoretical results suggest that the current through the trans-bent configuration is significantly larger than the corresponding linear one. The predicted on-off ratio of currents ranging from around 50 to 200 in the applied bias window [-1.5 V, 1.5 V] suggests that multiple bond compounds have attractive potential in molecular switch technology.