Ostermundigen has an area of 5.96 km² (2.30 sq mi).
Of this area, 1.9 km² (0.73 sq mi) or 32.0% is used for agricultural purposes, while 1.52 km² (0.59 sq mi) or 25.6% is forested.
Of the rest of the land, 2.55 km² (0.98 sq mi) or 42.9% is settled (buildings or roads) and 0.01 km² (2.5 acres) or 0.2% is unproductive land.

Of the built up area, industrial buildings made up 3.2% of the total area while housing and buildings made up 25.8% and transportation infrastructure made up 9.1%.
Power and water infrastructure as well as other special developed areas made up 2.0% of the area while parks, green belts and sports fields made up 2.9%.
Out of the forested land, 24.4% of the total land area is heavily forested and 1.2% is covered with orchards or small clusters of trees.
Of the agricultural land, 25.1% is used for growing crops and 6.2% is pastures.

The municipality is located in the lower Worblental (Worblen valley) at the foot of the Ostermundigenberg and the Hättenberg.
It is part of the agglomeration of Bern.
Until 1983 it was part of the municipality of Bolligen.

On 31 December 2009 Amtsbezirk Bern, the municipality's former district, was dissolved.
On the following day, 1 January 2010, it joined the newly created Verwaltungskreis Bern-Mittelland.
Ostermundigen has an area of 5.96 km² (2.30 sq mi). Of this area, 1.9 km² (0.73 sq mi) or 32.0% is used for agricultural purposes, while 1.52 km² (0.59 sq mi) or 25.6% is forested. Of the rest of the land, 2.55 km² (0.98 sq mi) or 42.9% is settled (buildings or roads) and 0.01 km² (2.5 acres) or 0.2% is unproductive land.
Of the built up area, industrial buildings made up 3.2% of the total area while housing and buildings made up 25.8% and transportation infrastructure made up 9.1%. Power and water infrastructure as well as other special developed areas made up 2.0% of the area while parks, green belts and sports fields made up 2.9%. Out of the forested land, 24.4% of the total land area is heavily forested and 1.2% is covered with orchards or small clusters of trees. Of the agricultural land, 25.1% is used for growing crops and 6.2% is pastures.
The municipality is located in the lower Worblental (Worblen valley) at the foot of the Ostermundigenberg and the Hättenberg. It is part of the agglomeration of Bern. Until 1983 it was part of the municipality of Bolligen.
On 31 December 2009 Amtsbezirk Bern, the municipality's former district, was dissolved. On the following day, 1 January 2010, it joined the newly created Verwaltungskreis Bern-Mittelland.
Ostermundigen