Jaguars (Panthera onca) suffer from the negative effects of roads, mostly significant habitat fragmentation and increased risk of mortality due to vehicle collisions. In Mexico records of jaguars killed on roads are scarce and mostly anecdotal. The Calakmul-Balam-Kú jaguar population is the most important jaguar population in Mexico, but it is threatened by an extensive road network in which Federal Highway 186 Escárcega–Chetumal (hereafter called Hwy. 186) serves as the main road in the region. As part of a study to determine the diversity and abundance of medium- and large-sized mammals around Hwy. 186, we set 47 camera traps during 2019 and obtained pictures of 2 male jaguars on both sides of the road, evidence that these animals were crossing the highway. Also, later in 2020 we found the road-killed carcass of one the jaguars that we had previously documented crossing the highway. These empirical observations occurred in areas where landscape models implemented as far back as 2010 had predicted jaguar crossing sites on Hwy. 186 and where wildlife-safe road-crossing infrastructure has been proposed but so far not installed.