Microcantilever array biosensor shows peculiarities of high speed, trace detection and label-free in bioanalysis. A method to increase the detection sensitivity and to speed up analysis of microcantilever array biosensor is reported. The gold covered microcantilever array immobilized by DNA probes is applied as a microcantilever array biosensor with electrostatic field. Microcantilever arry is acted as anode in hybridization solution cell where DNA molecules are removed to and congregated around anode, so the DNA hybridization is enhanced. The data demonstrated: (1) the time of DNA hybridization on the cantilever system drived by direct electric field was no more than 3 min; (2) the detection sensitivity was improved from 30 μg/L to 300 ng/L level.