Four fire engines and around 25 firefighters tackled a fire in a field on Kings College Road in Ruislip.
Around one hectare of grass was damaged by fire. There are currently no reports of any injuries.
Today's fire comes as London experiences high temperatures with a yellow Heat Health alert issued by the UK Health Security Agency. During this type of weather, the risk of grass fires increases and the Brigade is asking the public to follow crucial safety advice that will help protect themselves, others, the environment and their property.
London Fire Brigade Assistant Commissioner for Prevention and Protection, Craig Carter, said: "We know many Londoners will want to enjoy the nice weather by visiting a park or open space. However, we’re asking people not to take disposable barbecues with them as they can cause grass fires, especially in hot weather when the ground is dry. These fires are unpredictable and can spread rapidly, causing a significant amount of damage.
"Don’t be tempted to barbecue on your balcony either. Balconies can contain combustible materials which can pose a risk to those barbecuing and others living nearby.
"If you are having a barbecue, never leave it unattended and be careful where it’s positioned. Aim for level ground and keep barbecues well away from anything flammable like sheds, fences, trees or tents."
As well as disposable barbecues, discarded smoking materials and leftover rubbish also pose a huge fire risk. People are asked to ensure their rubbish is placed securely inside a bin or to take it home with them. If you have had a cigarette, please make sure that it is completely out.
The Brigade's 999 Control Officers took over 15 calls to the blaze. The Brigade was first called at 2007 and the fire was under control by 2250. Crews from Harrow, Ruislip and Northolt fire stations attended the scene.