Local disciplinary organs across China investigated 265 prefecture-level officials in 2015, 2.5 times the number in 2014.
Another 1,386 county-level officials were also investigated, 1.65 times the figure for 2014 and 15 times the number investigated in 2013, the People's Daily reported on Sunday.
As a result, 41 prefecture-level and 311 county-level officials were sanctioned by the Communist Party of China (CPC)'s organizational departments.
Since the 18th CPC National Congress in late 2012, inspectors have completed eight rounds of checks, covering all major provincial-level governments, large state-owned enterprises and central financial institutions.
Expanding the supervision net, the inspection is extending to the provincial and municipal level to promote good work styles and fight indiscipline, including corruption.