After his father was diagnosed with bowel cancer last year, O' Donnell decided to raise funds for a cause close to his heart.
He said: "One reason I'm supporting the Movember campaign is because my dad was diagnosed with cancer last year.
"We found out he had the disease just before Christmas so it's been a pretty tough year. He had an operation during the summer to remove the tumour so he's back home recovering now.
O' Donnell has set-up a page on the official Movember website, where people can donate money. He currently has £90 but is hoping to raise more money with the help of fans.
He continued: "After my dad was diagnosed, I remember him saying how much of an epidemic cancer is now.
"Years ago it came as a shock but so many people are being diagnosed with it now and there's not many people who haven't been affected by the disease in one way or another.
"Any money we can raise towards fighting the disease and finding the cause, would be amazing."
The 26-year-old, who joined Warriors from Rotherham Titans during the summer, will make his first start for Warriors this Sunday as the side travel to London Wasps in the LV= Cup.
Warriors currently top Pool 2 of the competition after a bonus-point victory over Scarlets last weekend and O' Donnell is excited about making his full debut. .
He stated: "I'm really looking forward to starting my first game this weekend. I've worked hard with the coaches in training and I've seen massive improvements in my game over the last few months.
"We feel we've got a bit of a score to settle after our league defeat a few weeks ago. We had a number of opportunities in that game where we could have won the game but it didn't work out that way.
"We haven't got the pressure of the Aviva Premiership on our shoulders so we will be able to go out and play a bit more and hopefully get the result we want."
To donate money to support the Movember campaign, please visit O' Donnell's Movember page.