Leszek of Dobrzyń

Leszek of Dobrzyń (pl: Leszek dobrzyński; bef. 1302 - bef. 10 July 1316), was a Polish prince member of the House of Piast and Duke of Dobrzyń during 1312-1316 with his brothers.

He was the eldest son of Siemowit of Dobrzyń and Anastasia, daughter of Leo I of Halych-Peremyshl.

The only known fact about him was the his mention in the testimony of Jan of Kisielew during the Polish-Teutonic trial in Warsaw in 1339; because this is the only contemporary source who named him, his existence is a matter of dispute between historians. If he was a real person, certainly died young, in or before 1316, still under the regency of his mother and uncle Władysław I.