John James Joass (1868 – 10 May 1952) was a Scottish architect, born in Dingwall, Scotland.
His father William Cumming Joass was an established architect in that town.
In 1905, the partnership was working on the remodeling of a country house in Tapeley Park, in the village of Instow, Devon.
In 1926 Joass was commissioned to provide an extension to Chartered Accountants Hall, which had originally been designed by Belcher and constructed in the 1890s.
His paternal uncle was the antiquarian and geologist Rev James Maxwell Joass, minister of Golspie.