Letov S-328 in Slovak Service

In March 1939, Germany occupied the Czech part of Czechoslovakia and Slovakia declared its independence. Consequently, Slovakia inherited a number of Letov S.328 reconnaissance and light bomber biplanes that had been based in its territory. Additional aircraft were obtained from German stocks acquired during its annexation of Czechoslovakia, as well as 50 new built examples.

On 23 March 1939, Hungary invaded Slovakia in the Slovak–Hungarian War (23-31 March 1939). During the conflict, Letov S.328s conducted reconnaissance and bombing attacks on Hungarian troops.

When Slovakia participated in the German invasions of Poland in 1939 and the USSR in 1941, the S.328s were again used for bombing and reconnaissance missions. They were later used on anti-partisan operation in Ukraine. Following the Slovak National Uprising in September to October 1944, up to 11 Letov s.328s were seized by insurgents.