At the centre of the controversy is Margarete Bause, spokeswoman for human rights in the opposition Greens party.
The 60-year-old lawmaker has in the past accused the Chinese government of curbing human rights.
She has been particularly outspoken in her support for minorities, especially the Uighur community in Xinjiang.
Bause is part of a “Digital Agenda” delegation planning an official visit to China later this month.
Delegationsreise – Margarete Bause darf wohl nicht nach China einreisen https://t.co/ZzIY68foXJ
— Margarete Bause (@MargareteBause) August 3, 2019
Bause tweeted to say her committment to human rights was strengthened by the action.
The Greens politician said Chinese authorities have made it clear to her that the delegation cannot visit China as long as she is part of it, she told daily Süddeutsche Zeitung.
“It is unacceptable for the German Bundestag to be held to ransom,” she was quoted as saying, referring to the lower house of parliament.
A Bundestag spokeswoman confirmed to AFP that a letter was sent to the Chinese ambassador to Germany stressing that the chamber has sole responsibility for appointing delegation members.
Maria Adebahr, spokeswoman for Germany's foreign office, said there had been no “formal rejection” from the Chinese and that talks were ongoing.
Angela Merkel's deputy spokeswoman Ulrike Demmer said Monday that the German government was committed to dialogue with China “at all levels”, especially on “difficult issues”.