<p>The present invention relates to a power miter saw (30) with a quick actuating mechanism for a movable guard (5). The mechanism comprises a mounting arm (7), a fixed guard (3), a drive means and a circular saw blade (6). The movable guard (5) is pivotally connected to the fixed guard (3). The movable guard (5) is pivotally connected to the front end of the actuating link (2) by a second guiding member (4). The rear end of the actuating link is movably connected to the mounting arm (7). A first guiding member (1) is disposed on the rear end of the actuating link (2) and the mounting arm has a first arcuate slide slot with which the first guiding member engages. When the fixed guard moves together with the saw unit downwardly, the actuating link pivotally engages the first slide slot and actuates the movable guard rapidly to open. The movable guard of the present invention can be easily manufactured and conveniently assembled or adjusted so as to reduce the cost.
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