Karin Strenz, 53, was flying back to Frankfurt from Cuba with her husband when she lost consciousness on Sunday.
The plane made an emergency landing at Shannon Airport, Co Clare, Ireland, at about 7:30am.
Rescuers were unable to save Strenz and she was pronounced dead at hospital.
It remains unclear what caused her death, but a post-mortem will be carried out to establish why she lost consciousness.
It was also unclear why she had travelled to Cuba.
Karin Strenz, 53, a lawmaker with German Chancellor Angela Merkel’s party, has died after collapsing on a plane during a flight home to Germany on Sunday
Strenz was flying back to Frankfurt from Cuba with her husband when she lost consciousness, forcing the plane to make an emergency landing in Ireland
Rescuers were unable to save Strenz and she was pronounced dead at University Hospital in Limerick
Garda HQ at the Phoenix Park in Dublin confirmed a woman on a flight that had landed at Shannon Airport had later died, but made no further comment, the Irish Times reported.
A statement said: ‘Gardaí and emergency services were alerted to a medical emergency on board a flight which landed at Shannon Airport, Co Clare, at approximately 7.30pm,’ it said of the Sunday morning landing.
‘A woman (50s) was taken to University Hospital Limerick from the aircraft. The woman was pronounced deceased a short time later. Arrangements have been made for a postmortem to take place.’
Strenz had been a member of the German parliament since 2009, representing a constituency in the northeastern state of Mecklenburg-Western Pomerania.
She didn’t plan to seek re-election in Germany’s September 26 election.
Strenz and three other centre-right politicians were targeted in raids by prosecutors investigating alleged money transfers from Azerbaijan
Strenz and two other lawmakers were under investigation by prosecutors over alleged money transfers from Azerbaijan.
The group of three centre-right politicians allegedly took money from the authoritarian, former-Soviet republic and in return lobbied on the state’s behalf.
If found guilty, she faced up to five years in prison.
Strenz was also fined more than £17,000 by the Bundestag earlier this year after she admitted in 2019 that a company she ran had accepted donations from an undisclosed source.
The company, Line M-Trade, reportedly received nearly £13,000 in donations from the unidentified source in 2014 and 2015.
During the same period, Strenz voted against a Council of Europe motion that called for on Azerbaijan to release political prisoners.
In 2018, Strenz was banned for life from the Council of Europe, the European human rights body, after a report found evidence of corruption.
Strenz was also fined more than £17,000 by the Bundestag earlier this year after she admitted in 2019 that a company she ran had accepted donations from an undisclosed source