Bolken is a municipality in the district of Wasseramt in the Canton of Solothurn in Switzerland .

Bolken is first mentioned in 1429 as ze Bollikon.

Bolken has an area, as of 2009, of 2.12 square kilometers (0.82 sq mi). Of this area, 1.37 km2 (0.53 sq mi) or 64.6% is used for agricultural purposes, while 0.46 km2 (0.18 sq mi) or 21.7% is forested. Of the rest of the land, 0.26 km2 (0.10 sq mi) or 12.3% is settled (buildings or roads), 0.04 km2 (9.9 acres) or 1.9% is either rivers or lakes.

Of the built up area, housing and buildings made up 6.6% and transportation infrastructure made up 5.7%.