Oberwil-Lieli is a municipality in the district of Bremgarten in the canton of Aargau in Switzerland.

Their rights came in the 14th century to the lords of Schönenwerd and the knight Heinrich Biber, but in 1352 they went to the Family Stagel of Zurich.

The Kollatur (first mentioned in 1186) went out from under the authority of Engelberg Abbey in 1303 to the hospital at Konstanz and in 1527 was sold to Bremgarten.

Of the rest of the land, 14.9% is settled (buildings or roads) and the remainder (0.2%) is non-productive (rivers or lakes).

[4] The municipality is located in the Bremgarten district on a terrasse in the Reuss river valley.

The blazon of the municipal coat of arms is Argent a Pear Tree eradicated Vert fructed Or and Coupeaux of the second.

The pear tree on the flag of Oberwil-Lieli is from the Holzbirrliberg, a mountain where the village is located.

[4] The age distribution, as of 2008[update], in Oberwil-Lieli is; 231 children or 11.1% of the population are between 0 and 9 years old and 213 teenagers or 10.2% are between 10 and 19.

[9] About 67% of the total households were owner occupied, or in other words did not pay rent (though they may have a mortgage or a rent-to-own agreement).

[11] The historical population is given in the following table:[3] As of  2007[update], Oberwil-Lieli had an unemployment rate of 1.4%.

[4] From the 2000 census[update], 725 or 41.9% were Roman Catholic, while 663 or 38.3% belonged to the Swiss Reformed Church.

Nearby secondary schools:[14] In 2015, the mayor of Oberwil-Lieli at that time, Andreas Glarner, announced that the village would not agree to house its allocation of 10 asylum seekers and instead pay a CHF 290,000 annual compensation.