Very little is known about marking behavior of the endangered Andean bear (Tremarctos ornatus). Here, we present a first detailed description of Andean bear marking behavior obtained using camera traps. From November 2012 to April 2013, we inspected 16 bear trails in the Napo province of eastern Ecuador, and installed camera traps (n = 3) at marking sites to document their marking behavior. We obtained 22 video recordings of Andean bears, all of which were captured during daytime. Almost all recordings (n = 18) contained behavior associated with marking. Tree-rubbing was the main behavioral display at marking sites, and consisted of 4 common activities: (1) tree-sniffing, (2) rubbing the neck and/or shoulders, (3) rubbing the flanks, and (4) rubbing the back. Bears also claw-marked and urinated while rubbing trees. We only observed scent-marking from males. Consistent with other bear species, we suggest that Andean bears communicate intra-specifically through their marking behavior.