The Battle of France in 1940 revealed its inadequate penetration capability against French and British heavier tanks, particularly the Char B1, and especially the Matilda II, receiving the derisive nicknames "Heeresanklopfgerät" ("army door-knocking device") or "PanzerAnklopfKanone" ("tank door-knocking cannon") from its crews, but it sufficed to defeat the bulk of the Allied armor in the campaign.

The introduction in 1942 of the Stielgranate 41 shaped charge gave it the ability to punch through the armor of any Allied tank, but the ammunition's short range made the Pak 36 crews vulnerable to enemy fire and could not solve the gun's basic obsolescence.

German paratroopers employed the gun due to its low weight and consequent high maneuverability.

[1] During the May 1940 Western Campaign, the Pak 36, being a relatively small-calibre weapon, was found to be inadequate against heavy Allied tanks like the British Mk II Matilda and the French Char B1 and Somua S35, although it was effective against the most common light tanks of the era, such as the French R35 which represented the majority of the armoured vehicles during the Battle of France.

'army door-knocking device') by German anti-tank crews for its inability to affect the T-34 aside from notifying its presence by futilely bouncing rounds off its armour, regardless of the angle or distance.

The guns were also passed off to the forces of Germany's allies fighting on the Eastern Front, such as the 3rd and 4th Romanian Army.

In February 1942,[10] the introduction of the Stielgranate 41[11] shaped charge meant that the Pak 36 could now penetrate most armour, although the low velocity of the projectile limited its range.

The gun's low weight meant that it could be easily moved by hand, and this mobility made it ideal for their purpose.