| Mažeikiai District Municipality | |
| Native Name: | Mažeikių rajono savivaldybė |
| Native Name Lang: | lt |
| Settlement Type: | Municipality |
| Image Map1: | MazeikiuRajonoSeniunijos.png |
| Map Caption1: | Map of Mažeikiai district municipality |
| Subdivision Type: | Country |
| Subdivision Name: |  Lithuania |
| Subdivision Type1: | Ethnographic region |
| Subdivision Name1: | Samogitia |
| Subdivision Type2: | County |
| Subdivision Name2: | Telšiai County |
| Parts Style: | para |
| Parts Type: | Elderships |
| P1: | 9 |
| Seat Type: | Capital |
| Seat: | Mažeikiai |
| Unit Pref: | Metric |
| Area Total Km2: | 1220 |
| Area Rank: | 30th |
| Population Total: | 52,120 |
| Population As Of: | 2021[1] |
| Population Rank: | 10th |
| Population Density Km2: | auto |
| Population Density Rank: | 12th |
| Timezone1: | EET |
| Utc Offset1: | +2 |
| Timezone1 Dst: | EEST |
| Utc Offset1 Dst: | +3 |
| Postal Code Type: | Postal code |
| Postal Code: | LT-89100 |
| Area Code Type: | Telephone code |
| Area Code: | 443 |
| Blank Name Sec1: | Major settlements |
Mažeikiai District Municipality (Lithuanian: Mažeikių rajono savivaldybė, Mažėikiu rajuona savivaldībė) is located in the north-west of Lithuania, on the River Venta in Telšiai County. The administrative center of Mažeikiai District is the city of Mažeikiai. Its territory of 1220.2km2 is composed of 32km2 of towns and settlements, 22km2 of industrial enterprises and roads, 614km2 of agricultural lands, 273km2 of forests, and 68km2 of tracts of other designation. There is one urban and 8 rural elderates. In 2003, the population was 67,393. Of this number, 46,223 live in towns and 21,170 in villages.
It is situated in northern Samogitia. Mažeikiai District borders with the Republic of Latvia in the north, with Akmenė District Municipality in the east, with Telšiai District Municipality in the southeast, with Plungė District Municipality in the southwest and with Skuodas District Municipality in the west. Mažeikiai District stretches for 43.5km (27miles) east-to-west and 38km (24miles) north-to-south. Petraičiai village is the westernmost settlement, with Kalniškiai and Pakliaupė villages being the easternmost settlements. The northernmost is Giniočiai, while the southernmost is Pasruojė.
Mažeikiai District Municipality is one of the more populous administrative district municipalities (municipalities, covering mostly rural regions and smaller towns rather than major cities). The region is crossed by important railway lines: Liepāja (Republic of Latvia) – Šiauliai – Kaunas – Vilnius and Riga (Republic of Latvia) – Mažeikiai – Klaipėda. However, they are currently no longer used for passenger transportation.