The invention relates to the technical field of tower crane equipment, in particular to a small-size buttress. The small-size buttress can achieve fine adjustment and is wide in application range and convenient to use. The small-size buttress comprises a fixed base fixed to a wall. A U-shaped support is mounted on the fixed base. Straight pipes on the two side of an opening of the U-shaped support are each provided with a row of first positioning holes. The two straight pipes are sleeved with sliding sleeves correspondingly. The sliding sleeves are provided with first fixing holes corresponding to the first positioning holes. Bolts penetrate through the first positioning holes and the first fixing holes and then are locked through locknuts so that the sliding sleeves can be fixed to the straight pipes. The two sliding sleeves are connected through an intermediate support. A tower crane connecting support is mounted on the intermediate support.