Grand Secret is a suburb in the Charters Towers Region, Queensland, Australia.

In 2010, the central suburb of Charters Towers City was created by combining the former suburb of Lissner with land excised from Queenton and Grand Secret.

[4][5] In the 2011 census, Grand Secret had a population of 145 people.

[6] In the 2016 census, Grand Secret had a population of 168 people.

The nearest primary school is Charters Towers Central State School in neighbouring Charters Towers City to the east.