Abstract: Aiming at the poor stability of toppling, sliding and slanting supports, instability mechanism of support was obtained through mechanical analysis of single and several supports at different working conditions. The instability of supports mainly occurred during dropping and moving. The stability of supports can be guaranteed by rational management measures. By comprehensive solutions of rational moving sequence, making the neighboring supports stable before moving supports, enlarging the width of side guard plate, taking full advantage of side and bottom jacks to adjust the condition, the supports in greatly inclined seam remains are stable.