Strychnos innocua (Loganiaceae) is a valuable timber tree, used locally as traditional medicine to treat several diseases such as gonorrhea, snake bites, conjunctivitis and diarrhea; fruits and leaves of this plant are also fed by human and cattle. This plant is attacked by a psyllid which causes serious damage by inducing leaf galls, defoliation and necrosis. The aim of this work is the description and identification of the psyllid associated with Strychnos innocua in Cameroon, and thus contributes to the psyllid biodiversity study in Cameroonian fauna. The study was carried out in Adamawa Region of Cameroon, on wooded savannah of Wack cliff, from July 2015 to July 2016. The psyllid of Strychnos innocua, Diaphorina strychnos sp. nov., can be diagnosed by: the stage V larva, antenna composed of eight segments and the antennal segments: 3, 4, 6 and 7, each bears a single subapical rhinarium; abdomen bears a circular circumanal with a single row of waxy rounded pores and presents a deep internal depression on its anterior margin; posterior abdominal margin bears lanceolate setae. In adult, trapezoidal vertex; rhinaria of flagellomeres 2 and 4 of antenna are surrounded by simples setae; forewing is covered by irregular patches on the entire surface; costal and sub-costal veins (C+Sc) of the hingwing bear four setae before the costal break and six plus five setae and hamelus after the costal break (4+6+5+1); metathoracic leg has a short and rounded meracanthus; the apical part of metatibia bears seven spurs (3 internals and 4 externals) and the metabasitarsus bears two spurs (one internal and one external); cylindrical paramere with a slightly narrowed apical portion which is incurved subapically on internal margin; female proctiger is triangular with a large proximal part and narrow apical part, rounded apex; female sub-genital plate is formed of two lobes: a proximal large lobe and a distal pointed lobe. Comparing Diaphorina strychnos with the specimens recorded previously elsewhere, it is morphologically different from them and can be reported as new specie in the Diaphorina Löw, 1880 genus.