Gmina Osielsko is a rural gmina (administrative district) in Bydgoszcz County, Kuyavian-Pomeranian Voivodeship, in north-central Poland. Its seat is the village of Osielsko, which lies approximately 9 kilometres (6 mi) north-east of Bydgoszcz.
The gmina covers an area of 102.89 square kilometres (39.7 sq mi), and as of 2014 its total population is 12,239. Osielsko is the richest gmina in Kuyavian-Pomeranian Voivodeship. Osielsko's main source of wealth is personal income tax paid by inhabitants of this gmina.
Gmina Osielsko contains the villages and settlements of Bożenkowo, Czarnówczyn, Jagodowo, Jarużyn, Jarużyn-Kolonia, Maksymilianowo, Myślęcinek, Niemcz, Niwy, Osielsko, Strzelce Leśne, Wilcze and Żołędowo.
Gmina Osielsko is bordered by the city of Bydgoszcz and by the gminas of Dobrcz, Koronowo and Sicienko.
There are 4 Roman Catholic parishes in Gmina Osielsko:
parafia św. Maksymiliana Kolbego – Maksymilianowo
parafia MB Wspomożenia Wiernych – Niemcz
Parafia Narodzenia Najświętszej Maryi Panny w Osielsku – Osielsko
parafia Podwyższenia Krzyża Świętego – ŻołędowoOsielsko is also a seat of dekanat Osielsko (administrative district of the Roman Catholic Church).