A mountain brigade had the following structure: 6 battalions, one mountain artillery group (1 or 2 battalions of 75 mm or 76.2 mm mountain guns and one battalion of 100 mm mountain howitzers) and one mountain pioneer battalion.

The battalion had 3 rifle companies, each company 3 platoons and each platoon 3 sections. It also had a heavy weapons company made up from 3 machine-gun platoons (4 Schwarzlose/ZB-53 each) and one mortar platoon (4xBrandt 81.4 mm). The rifle platoon had one 60 mm Stokes Brandt mortar and 3xZB light machine-guns, one for each section.

Like the cavalry, the mountain troops had higher training and professionalism than the regular infantry. The initiative at battalion level was more developed. They were proper suited for fighting on difficult terrain, but their lack of artillery made them vulnerable in open field. The Mountain Corps also had a mounted battalion, a mountain train battalion and a hospital company.

At the beginning of the war the Mountain Corps was made up of the 1st, 2nd and 4th Mountain Brigade. The 3rd Mountain Brigade was stationed on the frontier with Hungary. At the end of the 1941 campaign, the 2nd Mountain Brigade was brought back to Romania and the 1st and 4th Mountain Brigade remained in Crimea. During the winter, an Expeditionary Skier Group was formed from some of the troops of the 3rd Mountain Brigade. The 5th and 6th Mountain Battalions became the 25th and 26th Skier Battalions. The Group also had a communications platoon, a pioneer platoon, an AA gun platoon (4x20 mm), an AT gun company (6x47 mm) and a 75 mm mountain howitzer battalion. For transportation the Group had 60 donkeys, 60 sleds and 6 trucks. In January 1942, the Skier Group was sent to Crimea and subordinated to the 1st Mountain Brigade. But soon it was put under the direct command of the 11th German Army and used in the fights around Izyum.

During the same winter, the 2nd and 3rd Mountain Brigade were completely rearmed. The old WWI artillery pieces were replaced with modern German guns. The 1st and 4th Mountain Brigades, which were on the front, received field guns instead of mountain guns. Because they were involved in the first siege of Sevastopol, they were strengthened with two 100 mm howitzer battalions.

On 15 March 1942, the mountain and cavalry brigades became divisions. This was a political, but just decision. The Italian and Hungarian divisions had 6 battalions like the Romanian brigades. This measure was taken in order to show the real size of the Romanian contribution to the war effort against the USSR.

In July 1942, the 2nd and 3rd Mountain Divisions were sent on the front and took part in the campaigns in the Caucasus and the Kuban.

During the winter of 1942/1943, the 1st Mountain Division was also modernized. The 4th Mountain Division never got to replace its old guns, because it was disbanded in November 1944. After the battle of Stalingrad, the 18th Infantry Division was transformed into the 18th Mountain Division. Its regiments were renamed mountain groups (18th, 90th and 92nd) and the battalions received new numbers (27th-35th). The 1st, 2nd and 3rd Mountain Divisions were retreated in Crimea and the 4th Mountain Division was joined with the 24th Infantry Division to form the 4/24th Infantry Division.

In May 1944, only 60% of the mountain troops in Crimea were evacuated. From these there were formed the 101st, 102nd, 103rd and 104th Mountain Brigades. Each one had 4 battalions, one 120 mm mortar company, 2 mountain gun battalions (the first one had 8x75 mm mountain howitzers and 2x20 mm AA machine-guns and the second had 4x100 mm mountain howitzers) and a work platoon. It was about one fourth of a regular mountain division.

On the 1st June the 4/24th Infantry Division was transformed into the 4th Mountain Division. The 1st and 3rd Mountain Divisions were deployed on the frontier with Hungary. The lack of a reserve of the mountain troops (the infantry and the cavalry had the training divisions) meant that all the replacements came from the frontier-guards or from the gendarmerie. Thus the quality of the mountain troops decreased, but they still were above the infantry.

After 23 August 1944, the 101st and 102nd Mountain Brigades and the 4th Mountain Division managed to escape capture by the Soviets. The 103rd and 104th Mountain Brigades were not so lucky. The 103rd Mountain Brigade was transformed by the Soviets into an ad hoc unit: the 103rd Mountain Division (the 17th Infantry Regiment, the 8th Frontier-guard Regiment, the 11th and the 16th Artillery Regiments). It was subordinated directly to them and was disbanded in October 1944.

The 2nd and 3rd Mountain Divisions participated in the battles in Transylvania and then in Hungary.

At the beginning of November, according to the armistice protocol, the 1st and 4th Mountain Divisions were disbanded, as well as the 4 mountain brigades and the 18th Mountain Division was once again transformed into the 18th Infantry Division. The structure and equipment (there were fewer mountain guns compared to field guns) of the mountain divisions that survived the process was very close to the one of the infantry divisions.