A micro tubular solid oxide fuel cell (SOFC) bundle was developed based on new concept. The anode-supported micro tubular SOFCs with the cell configuration, La0.6Sr0.4Co0.2Fe0.8 O3-δ (LSCF) - Ce0.9Gd0.1O 2-δ (CGO) cathode / CGO electrolyte /Ni - CGO anode were fabricated and were bundled by a porous LSCF current collecting cube 1 cm on a side. The power generation test of the fabricated SOFC bundle was carried out under pressurized conditions. Using wet 30%H2 / N2 mixture gas and air, the cubic power density of the bundle at 500°C was 0.47 Wcm-3 at 0.4Acm-2, atmospheric pressure (0.1 MPa). With increasing operating pressure, the performance has been improved, and the cubic power density finally reached to 0.66 Wcm-3 at 0.6MPa. Pressurization effect for the power improvement was brought about by the open circuit voltage enhancement and reduction of the polarization resistance.