The First Battle of El Alamein 1–July 31 1942 was a battle of the Western Desert Campaign of World War II, fought between the German–Italian Afrikakorps commanded by Erwin Rommel and the British Eighth Army, commanded by Claude Auchinleck.

Following the defeat at the Battle of Gazala in June 1942, the Eighth Army had retreated from Mersa Matruh to the Alamein Line in Egypt, a 40 mile (60 km) gap between the town of El Alamein on the Mediterranean coast to the north and the Qattara Depression in the desert to the south.

On July 1 the Afrikakorps attacked. The Allied line near El Alamein was not overrun until the evening and this hold up stalled the Axis advance. On July 2 Rommel concentrated his forces in the north, intending to break through around El Alamein. Auchinleck ordered a counter-attack at the centre of the Axis line but the attack failed. The Allies also attacked in the south and were more successful against the Italians. As a result of the Allied resistance, Rommel decided to regroup and defend the line reached.

Auchinleck attacked again on July 10 at Tel el Eisa in the north and over one thousand prisoners were taken. Rommel's counter at Tel el Eisa achieved little. Auchinleck then attacked again in the centre at the Ruweisat Ridge in two battles (the First and Second Battles of Ruweisat on July 14 and July 21). Neither battle was successful and the failure of armour to reach the infantry in time at the Second Battle led to the loss of 700 men. Despite this another two attacks were launched on July 27. One in the north at Tel el Eisa was a moderate failure. The other at Miteiriya was more calamitous, as the minefields were not cleared and the infantry were left without armour support when faced with a German counter-attack.

The Eighth Army was exhausted, and by July 31 Auchinleck ordered an end to offensive operations and the strengthening of the defences to meet a major counter-offensive.

The battle was a stalemate, but the Axis advance on Alexandria (and then Cairo) was halted. A second attempt by Rommel to bypass or break the Commonwealth position was repulsed in the Battle of Alam Halfa in August, and in October the Eighth Army, now commanded by Bernard Montgomery, decisively defeated the Axis forces in the Second Battle of El Alamein.