In a poll carried out by YouGov for Channel 5's OK! TV, a sample of 302 viewers were asked to choose from a list of events from past series.
The winning moment, which secured 24% of the vote, came during the 2006 series when actress Lenska asked the then-MP to assist her in preparing for a task. Galloway proceeded to mimic a cat, purring and licking imaginary milk from her hands.
Watch George Galloway pretending to be a cat below:
Jackie Stallone's shock entrance to the Celebrity Big Brother house in 2005 finished second, with 17% choosing her arrival as their most memorable moment.
Both Vanessa Feltz's 2001 meltdown and John McCririck's 2005 underwear protest polled 9%, while Alex Reid's victory in the final series last year scored 8% of the vote.
Ulrika Jonsson and Verne Troyer's 'Endless Love' duet during the 2009 series and Jack Dee's attempted escape from the compound in 2001 followed behind.
Watch Ulrika Jonsson and Verne Troyer's duet below:
However, 14% of those polled chose none of the selected moments as their 'Most Memorable', with a further 4% opting for the 'Don't Know' option.
The full results can be seen tonight on Channel 5's OK! TV from 6.25pm.
Celebrity Big Brother, hosted by Ultimate Big Brother champion Brian Dowling, launches tonight at 9pm on Channel 5.
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