Thornlands is one of the 21 bayside suburbs of the Redland Shire, approximately 25 kilometres East-South-East of Brisbane. It is primarily a residential area. As at June 2003, Thornlands was estimated to be home to 8,754 people, with the majority of these of working age.
Thornlands began as part of the area then encompassed by Cleveland, and was leased (along with most of the land between Ormiston and the Logan River), to Joseph Clarke. He relinquished his lease in 1858, allowing small farmers to settle in the area.
The area took the name Thornlands after George Thorn, a major landholder in the area, whose lands were subdivided around 1900. The area was settled, like the surrounding suburbs, primarily by farmers, mostly growing fruit such as citrus, bananas and mangoes. Thornlands State school was founded in 1910.
The area is now primarily suburban residences, with the southern parts rural residences, comprising larger landblocks. The population is growing rapidly due to new housing developments.