It was not immediately clear whether the executive Leon Wang was in the custody of the Chinese government. When asked about Wang's whereabouts, a company spokesperson only reiterated that the executive was under investigation.
The Anglo-Swedish company has for years had one of the strongest market positions among western drugmakers in China, the world's No.2 pharmaceuticals market behind the United States. It has invested heavily in the country, announcing plans last year to build a $450 million factory and more recently signing a number of licensing deals with Chinese companies.
In a statement, the drugmaker said its Chinese operations were "under the leadership of the current general manager of AstraZeneca China," without providing further details.
"If requested, AstraZeneca will fully cooperate with the investigation", the statement read.
AstraZeneca shares were down 5.2% at 1429 GMT.
In September, China detained five of AstraZeneca's current and former employees for questioning. At the time, Bloomberg News reported that the employees were detained for questioning about potential illegal activities.
The company has not given details about the detention in September and a spokesperson had no comment on Wednesday on the status of the employees being held.
Other foreign drugmakers have been subject to anti-graft investigation in China.
Last year, multinational pharma companies including South African drugmaker Aspen (APNJ.J) suffered business disruptions and lost orders from hospitals in China after Beijing intensified an anti-corruption drive in the nation's healthcare sector.
