( Сенгилеевский райо́н ) is an administrative and municipal district (raion
), one of the twenty-one
in Ulyanovsk Oblast
. It is located in the center of the oblast
. The area of the district is 1349 km2. Its administrative center
is the town
. Population: 23,260 (2010 Census
); The population of Sengiley accounts for 29.9% of the district's total population.