Multiple authors, including several contemporary writers, described how the 551 CE Beirut earthquake affected the city of Byblos. These include Johannes Malalas, the author of the The Anonymous Itinerarium (erroneously) attributed to Antoninus of Piacenza, the anonymous author of Fragmenta Historica Tusculana, Pseudo‑Dionysius of Tell-Mahre, Theophanes, Michael the Syrian, and Bar Hebraeus.

A contemporary account is preserved by Johannes Malalas, who records that "the following cities suffered: 'Tyre, Sidon, Berytus, Tripolis, Byblus, Botrys and parts of other cities," and adds that "large numbers of people were trapped in them." Comparable lists of severely affected cities along the Phoenician littoral are preserved in the Fragmenta Historica Tusculana and Theophanes, which likewise describe widespread destruction and heavy loss of life in Tyre, Sidon, Berytus, Tripolis, and Byblos, among other settlements.

The destruction at Byblos is also described in the Anonymous Itinerarium (Antoninus of Piacenza), based on a visit approximately 5–15 years after the event, which states that the city was "destroyed with its inhabitants." Pseudo-Dionysius of Tell-Mahre also reports that "numerous cities collapsed" across Phoenicia, Palestine, and Arabia, including Byblos, describing widespread ruin affecting both towns and villages.

Some later accounts add evidence for tsunami effects. Michael the Syrian reports that "the sea withdrew two miles on itself, and ships lay on the ground" before inundating coastal cities such as Tripoli, Beirut, and Byblos, while Bar Hebraeus likewise notes submergence along the Phoenician coast.