Lynbrook, formerly part of Lyndhurst, is 35 km south-east of central Melbourne. Its boundaries are the Dandenong-Cranbourne railway (west) and the South Gippsland Highway and Hallam Road (east). Its northern limit is where the highway intersects with the Western Port Freeway and its southern limit is near the Marinda Park railway station.

Lynbrook began as a Vic Urban residential estate with about 2750 dwellings. Construction started in 1994, the year before the Merinda Park station opened. A decade passed before there was a primary school (2005), a shopping centre (2007) with a supermarket and 33 shops, and a Catholic primary school (2010). There is an extensive linear reserve along the western boundary, incorporating a wetland and a water purification lake that discharges into Dandenong Creek.

Lynbrook Railway Station, on the Cranbourne line between Lyndhurst and Marinda Park, was opened in 2012. The northern triangle of Lynbrook is mostly industrial, as is a vast area to the west in Dandenong South, which includes a land bank for a possible freight centre that would be connected by rail to the Port of Melbourne and to an enlarged Port of Hastings on Western Port Bay.

Lynbrook's census populations have been:

census date population
2006 4489
2011 6772

The median age of residents in 2011 was 32 years (Australia 37 years). The primary school's enrolment in 2014 was 982.