Philip Barker-Webb FRS (10 July 1793 – 31 August 1854) was an English botanist.
Born to a wealthy, aristocratic family, Barker-Webb was educated at Harrow School and Christ Church, Oxford. He collected plants in Italy, Spain, and Portugal, and was the first person to collect in the Tetuan Mountains of Morocco. En route to Brazil he made what was intended to be a brief visit to the Canary Islands, but he ended up stopping for a considerable time, returning after his Brazil expedition. The results can be seen in the nine-volume L'Histoire Naturelle des Iles Canaries, which he co-authored with Sabin Berthelot. In company with Berthelot, who had lived on the islands for some time, Webb collected specimens on the islands between 1828 and 1830. The text of L'Histoire Naturelle des Iles Canaries took 20 years to complete. Specialists such as Justin Pierre Marie Macquart wrote appropriate parts. Barker-Webb's herbarium was bequeathed to the Museo di Storia Naturale di Firenze in Florence, Italy.