The Battle of Caleb IV was a battle fought by the Klingon Empire in the 23rd century, shortly after the introduction of cloaking devices.

Caleb was attacked by two Klingon divisions led by Kang and Kor. Aboard the D5-class cruiser IKS Klothos, Kor outmaneuvered the defending Federation forces by attacking with an initial feint, and then returning with his full force, catching the Federation in the midst of their repair work.

A century later, during a similar attack on a Dominion base at Trelka V, Kor believed that he was back at Caleb IV. (DS9: "Once More Unto the Breach")

The Battle of Caleb IV is portrayed in the Star Trek Online expansion "Agents of Yesterday". Taking place in the year 2270, the mission is depicted as the first battle in which Klingons use cloaking devices. Kor has allied with time traveling Na'kuhl, but only in a sense that the Klingons are ready to turn against them when they are done. The Federation ships they captured are freed, but the fact that the Klingons drove them off and are able to destroy several of their ships, the player character's included, is enough for Kor.