Sumy (Ukrainian: Суми, Russian: Сумы) is a city on the Psel River in Ukraine, and the capital of the Sumy Oblast. As of 2004, the city's population is 283,700. It is served by Sumy Airport.

Sumy was founded in 1652 at the bank of the Psel River (a left tributary of the Dnieper) as a Cossack fortress. It was intended to protect Sloboda Ukraine from the Crimean Tatar attacks. After their attacks discontinued and the territory was incorporated into the Russian Empire, Sumy evolved into an important economical centre. During the German occupation of Ukraine during World War II (1941 – 1943), Sumy sustained heavy damage. The war over, destroyed parts of the city were rebuilt anew. Sumy has been a twin town of Celle, Germany since January 17, 1990.

The city centre was once dominated by the large cathedral of the Saviour's Transfiguration. It is a neoclassical structure of the 18th century, extensively repaired and reconstructed in 1858 and in the 1880s, when the 56 metre (180 ft) high bell tower was added. The interior features frescoes by Vladimir Makovsky and Klavdiy Lebedev. The Resurrection Church (1702), the oldest structure in the town, is still in fair preservation, owing to recent restoration work. The cathedral of the monastery of St. Pantaleon was erected in 1911 to a design by Aleksey Shchusev and is scored to resemble medieval monuments of Novgorod and Pskov.

The collection of Nikanor Onatsky Regional Art Museum in Sumy contains works of native and world art including a beautiful Dutch landscape by a painter of Jan van Goyen's circle.

Sumy was formerly home to the Ukrainian First League football team FC Spartak Sumy (now defunct).

The Ukrainian Premier League football club FC Kharkiv are currently leasing the city's state-of-the-art Yuvileiny Stadium.

- 1897 - 70,53% Ukrainians, 24,1% Russians 2,6% Jewish, 2.67% others
- 1926 - 80,7% Ukrainians, 11,8% Russians 5,5% Jewish, 2% others
- 1959 - 79% Ukrainians, 20% Russians, 1% others

The majority of residents are Christians (Eastern Orthodox, Roman Catholics and Protestants) There is also a Jewish minority.

From the beginning of 20th century, when in 1901 the Blessed Virgin Mary Annunciation Church was founded in Sumy, the town had become the center of North-East Ukrainian Catholicism.

After its consecration in 1911 and closing down by the authorities in two decades, the temple was used for non-religious purposes. The temple was restored as a Roman Catholic parish in May 1994, after the disintegration of the Soviet Union, and it was reconsecrated in spring 1998.

- Lev Yefimovitch Kerbel, Soviet sculptor
- Oleh Husyev, Footballer
- Bogdan Titomir, Soviet musician, rapper and DJ
- Viktor Yushchenko, President of Ukraine