Rufiji is one of the six districts of the Pwani Region of Tanzania.
It is bordered to the north by the Kisarawe and Mkuranga Districts, to the east by the Indian Ocean, to the south by the Kilwa District, Lindi Region and to the west by the Morogoro Region.
The district capital is the town of Utete on the southern banks of the Rufiji River.
The main ethnic groups that originate from the district are the Matumbi and Rufiji people.
According to the 2022 Tanzania National Census, the population of the Rufiji District was 159,906.