The German occupation of Belgium during World War II began on 28 May 1940, when the Belgian army surrendered to German forces, and lasted until Belgium's liberation by the Western Allies between September 1944 and February 1945. It was the second time in less than thirty years that Germany had occupied Belgium.

Despite being neutral at the start of World War II, Belgium and its colonial possessions found themselves at war after the country was invaded by German forces on 10 May 1940. After 18 days of fighting in which Belgian forces were pushed back into a small pocket in the north-west of the country, the Belgian military surrendered to the Germans, beginning an occupation that would endure until 1944. The surrender of 28 May was ordered by King Leopold III without the consultation of his government and sparked a political crisis after the war. Despite the capitulation, many Belgians managed to escape to the United Kingdom where they formed a government and army-in-exile on the Allied side.