The electrochemical behaviour of V-groove microelectrodes (10-100 mu m wide) was investigated and compared with that of planar band microelectrodes with the same sizes. The V-groove electrodes were fabricated by anisotropic etching on a [100] silicon wafer in KOH solutions. The cyclic voltammetric investigation at the V-groove electrodes revealed a different scan rate dependence of the peak current from that at the planar band microelectrodes. When the V-groove electrode was covered with a platinum plate lid electrode, the redox cycling between the two electrodes proceeds efficiently, exhibiting higher collection efficiencies than at the ordinary interdigitated microarray electrode with the same size. The high collection efficiency originated from the small effective diffusion length.