Chief superintendent Paul Money of West Yorkshire Police said a man aged 59 was interviewed voluntarily after complaints were made over the speech at a meeting in Leeds on Saturday August 2.
The Respect MP’s spokesman said Mr Galloway had co-operated with police.
The force said the matter would be referred to the Crown Prosecution Service when enquiries were completed.
The MP was said to have told the meeting: “We have declared Bradford an Israel-free zone. We don’t want any Israeli goods; we don’t want any Israeli services.”