It is roughly 9 acres (3.6 ha) in size, and contains a large central field bounded by trees, a children's playground, with a sandpit and splash pool, a multipurpose game court, two football pitches, and outdoor gym equipment.

In 1898, Thomas Baring, 1st Earl of Northbrook gifted part of his family's estate to public use in commemoration of the Diamond Jubilee of Queen Victoria.

In the past the park contained a larger playground, a paddling pool, a "legal" graffiti wall, a pond, a bowling green and a tennis court.

[5] An old stone sundial erected in May 1903, with engraving describing the gift of the land by Lord Northbrook to commemorate Queen Victoria's Jubilee, stands at the front of the park off the straight path,[2][3] but it is in disrepair.

[5] There is a small fenced playground with slides, swings, a zip line, a splash pool, a sandpit a roundabout and climbing frames in the northeast corner just inside the circular path,[5] it was constructed around 2000, and improved in 2012.

[3][5] The northwest corner is more overgrown and contains scrubland set aside as a wildlife area,[5] this is the site of the original children's playground.

[5] Just off the southwest corner of the central field there is a fenced multipurpose concrete game court,[5] where a pond was previously sited.

Later that year, in May 1903, an engraved sundial was erected at the front of the park, near the path between the two gates, to mark the gift of the land by Lord Northbrook, and the commemoration of Queen Victoria's Jubilee.

[3][19][20] In May 1903 permission for the construction of a sundial was granted, it was erected at the front of the park near the drinking fountain and the stone base was engraved with words describing the gift of the land by Lord Northbrook commemorating Queen Victoria's Diamond Jubilee.

[5][19][3] A small group of buildings including greenhouses were constructed at the very back of the park next to the western fence,[3][19] The part of the main field at the front of Northbrook Park was set aside as two sports fields, a bowling green in the northeast corner, and a tennis court in the southeast corner.

In 2010 a local 7-year-old boy named Ryan Wells sent a letter and photographs to the Mayor of Lewisham, Sir Steve Bullock, asking for Northbrook Park to be improved, with concerns over, lack of facilities in the park especially for older children, disrepair of playground equipment, litter, antisocial behaviour, dog faeces and aggressive dogs.

£50,000 of the raised money was awarded by National Lottery Community Fund, when the cause won the public's vote on People's Millions.

[23][24] Among the improvements were, erecting a short metal fence surrounding the central field to prevent dogs fouling on the play area or bothering playing children, and adding more equipment to the playground, such as a zipline, a splash pool, a basket swing, a net climbing frame, a roundabout for toddlers, a sandpit and a hammock.