The motion of DNA chain under electric field when it is in transient contact with the solid surfaces in aqueous Solution was studied by single molecule fluorescence microscopy at the total internal reflection geometry (TIRFM). In situ observation discovered that single lambda-DNA chains driven by electric field made transient contact with the solid sur-face and made hitting-sliding-leaving-like motion along the surface. By varying the surface chemistry from the negative-charged silanol group-rich surface to positive-charged amino group-rich surface, as well as hydrophobic surfaces, the dependence of DNA mobility on the surface-DNA inter-action was studied. The results show that a dependence of the mobility of DNA oil the surface polarity with respect to DNA itself. The study on different surfaces rich of silanol, amide, amino, and methyl groups show a sequence of DNA mobility of silanol > amide > amino. The mobility of DNA on methyl terminated surface was found to be similar to that on amino surface. (C) 2009 Wiley Periodicals, Inc J Polym Sci Part B Polym Phys 47 2541-2546, 2009