Linnaeus named the genus Tulbaghia after Rijk Tulbagh, who was the Governor of the Cape Colony from 1751 to 71. Rijk was born in Holland in 1699, enlisted with the Dutch East India Company and sailed to South Africa in 1716 and died in Cape Town in 1771. He corresponded with Linnaeus over a long period, and sent him more than 200 plant specimens. This genus was first described from material sent by Tulbagh in 1769. This species is named after Pretoria, a city in the Gauteng province, where most of the herbarium specimens were collected.

The genus Tulbaghia is only found in tropical and southern Africa. It consists of 28 accepted species. The best known ornamental species are T. violacea and T. simmleri. T. pretoriensis is the only one with taxonomic issues because it has been less studied.

This species was described by Vosa and Condy in 2006. The senior author, Vosa, came to the understanding that it was indeed a distinct species after he had already gathered some flowering Tulbaghia plants at the Monument Park grounds in Pretoria in September 1969, during the Oxford Botanical Expedition to eastern and southern Africa. At the time, these plants were thought to be similar to T. acutiloba. The plants he collected were grown in a temperate greenhouse in Europe where they flourished and blossomed. It immediately became apparent to him that these plants differed from T. acutiloba in some key details. He conducted a thorough examination of several herbarium specimens in the National Herbarium that were all obtained in and around Pretoria. What settled the issue was their chromosomal complement that indicated that their cytotaxonomic status differed from that of T. acutiloba. The type specimen chosen was the specimen collected by Gillian Condy, 24, in the National Herbarium, Pretoria, that was initially identified as T. acutiloba but accurately reflects the new species T. pretoriensis. The plate used as the iconotype for T. pretoriensis was that painted by Condy and published as T. acutiloba in 2001, in Flowering Plants of Africa, Plate 2164, which is based on the same specimen as the typus.