Constituting about 97 percent of the uniformed services, the army was the backbone of the armed forces. In early 1991, the army was organized into five revolutionary armies, which included thirty-one infantry divisions supported by thirty-two tank battalions, forty artillery battalions, twelve air defense battalions, and eight commando brigades. The army had expanded in size from 41,000 in 1974 to 50,000 in 1977, 65,000 in 1979, and 230,000 in early 1991. Ground order of battle was difficult to ascertain because of the army's rapid increase in size, frequent reorganization and redeployment of units, and constant reshuffling within the command structure. Units from the 200,000-member People's Militia augmented army divisions, especially in Eritrea and Tigray. The First Revolutionary Army had headquarters in Harer, the Second Revolutionary Army in Asmera, the Third Revolutionary Army in Kembolcha, the Fourth Revolutionary Army in Nekemte, and the Fifth Revolutionary Army in Gonder.

Ethiopian armored and mechanized units had approximately 1,200 T-54/55 tanks and 100 T-62 tanks, all of Soviet manufacture, and about 1,100 armored personnel carriers (APCs), most of which were of Soviet origin. However, combat losses and constant resupply by the Soviet Union, East Germany, North Korea, and other communist nations reduced the reliability of these estimates. Artillery units possessed a variety of Soviet-manufactured light and medium guns and howitzers, rocket launchers, and heavy mortars. Air defense units had quick-firing antiaircraft guns and surface-to-air missiles.

Because training in maintenance techniques had failed to keep pace with the influx of new equipment, weapons maintenance by the army was poor. Moreover, Ethiopian troops often deployed new weapons systems without understanding how to operate them. During the late 1970s and early 1980s, Ethiopia relied on Soviet and Cuban technicians to maintain military equipment and to provide logistical support. However, because of the reduction in military assistance, spare parts, and Soviet military advisers, as well as the withdrawal of all Cuban troops in the late 1980s, the army's maintenance ability again deteriorated. By 1991 most army equipment was operational only about 30 percent of the time.

Data as of 1991