The Kondo effect of a T-shape ligation between a single-wall carbon nanotube (SWNT) and a magnetic impurity is investigated theoretically. Hydrostatic pressure is applied, which leads to the opening of a gap in the density of states of a zigzag metallic nanotube. The effect of the pressure can be modeled by the Peierls instability; in this work, we consider the out-of-plane distortion. We use the tight-binding approach to calculate the SWNT Green's functions with the application of hydrostatic pressure. We investigate the disappearance of the Kondo peak as the gap opens. A strong influence of the pressure on the conductance is found, which is explained by the displacement of the Kondo peak from the chemical potential. The Kondo effect was reproduced using the atomic approach with U → ∞ developed previously.