The present invention discloses a glue-free anti-slip polyvinyl chloride floor brick which includes a polyvinyl chloride anti-slip layer having a bottom surface formed with a flexible thermal-pressed pattern by thermal pressing. The thermal-pressed pattern includes a plurality of continuously and repetitively connected, closed and non-equilateral hexagonal protruded ribs, which are characterized with a required flexibility by utilizing a special ingredient amount of the anti-slip layer and provided with an anti-slip coefficient of 1.5 by incorporating with non-equilateral hexagonal anti-slip patterns with special sizes and shapes, thereby enhancing the slip resistance of the floor brick to overcome the bottlenecks in plastic floor brick industries.