Trees or shrubs, evergreen (seldom deciduous for 1 or 2 months each year). Leaves entire or with short teeth; male flowers on inflorescences bearing 3(-7) flowers; 3-6(-9) styles; stigmas capitate; cup made of scales fused into concentric rings; stylopodium always conspicuous, with concentric rings; endocarp pubescent; aborted ovule at the apex of acorn.

Section 1 : Semiserrata Menits.
Reddish brown pubescence made of simple malgighian hairs; styles 1 to 3 mm long; acorn usually ellipsoidal, with broad rings of cupscales
__ Sub-section 1. Gemelliflorae Menits.
Mature leaves thin, hairless both sides; twigs soon glabrous; cup conical or saucer-shaped; style 1-1.5 mm long.
--- Q. gemelliflora Bl.
--- Q. kinabaluensis Soepadmo
--- Q. treubiana Seem.
--- Q. valdinervosa Soepadmo
--- Q. mespilifolia Wall. ex A.DC
--- Q. quangtriensis Hick. et A.Camus
--- Q. blakei Skan
--- Q. chrysocalyx Hick. et A.Camus
--- Q. platycalyx Hick. et A.Camus
__ Sub-section 2. Semiserratae Menits.
Mature leaves leathery, with usually prominent veins below, green adaxially, yellowish or whitish and often pubescent abaxially; cup with dense orange or yellowish tomentum, conical or cylindrical; style 1.5-3.5 mm long.
--- Q. elmeri Merrill
--- Q. longistyla Barnett
--- Q. semiserrata Roxburgh
--- Q. langbianensis Hick. et A.Camus - ssp langbianensis - ssp cambodiensis (Hick. et A.Camus) Menits.
--- Q. xanthoclada Drake
--- Q. macrocalyx Hick. et A.Camus
--- Q. kouangsiensis A.Camus
--- Q. tsoi Chun
--- Q. edithae Skan
--- Q. auricoma A. Camus
--- Q. pachyloma Seem.
--- Q. hui Chun
__ Sub-section 3. Chapensis Menits.
--- Q. chapensis Hick. et A.Camus
__ Sub-section 4. Chrysotrichae Menits.
Leaves with up to 1.6 mm long petiole; cup conical, minutely pubescent, up to 1 cm in diameter; acorn ellipsoidal-cylindrical.
--- Q. chrysotricha A.Camus
--- Q. merrillii Seem.
--- Q. arbutifolia Hick. et A. Camus
--- Q. litseoides Dunn
--- Q. phanera Chun
__ Sub-section 5. Eumorphae Menits.
Petiole up to 1 cm long; leaves leathery, entire, slightly wavy near apex, narrowly cuneate at base; cup conical or half-round, minutely pubescent; acorn conical to ovate.
--- Q. eumorpha Kurz - ssp eumorpha - ssp yaiensis Menits.

Section 2 : Oidocarpa Menits.
Leaves always entire, or nearly so, with pubescence made or small, stalkless or few armed, stellate hairs; 3 or 4 styles, 1-2 mm long; cup narrowed near peduncle.
__ Sub-section 1. Pseudoverticillatae Menits.
Petiole to 1 cm long; leaves crowded into pseudo-whorls, at the end of the twig; cup to 4 cm in diameter.
--- Q. pseudoverticillata Soepadmo
__ Sub-section 2. Oidocarpae
Petiole more than 1 cm long; leaves soft, without wax beneath.
--- Q. oidocarpa Korth.
--- Q. subsericea A. Camus
--- Q. kerangasensis Soepadmo
--- Q. sumatrana Soepadmo
__ Sub-section 3. Niveae Menits.
Leaves thick, usually with a waxy coat abaxially; petiole 1 to 4 cm long.
--- Q. nivea King
--- Q. percoriacea Soepadmo
--- Q. lowii King

Section 3 : Cyclobalanoides Menits.
Glabrous mature leaves and twigs; young leaves with very small simple and stellate hairs; leaves entire, broadly elliptical to lanceolate; cup conical with dentate or crenate rings; 3 styles 1 mm long; acorn ellipsoidal, ripenning in 2 years; young twig covered with lenticels.
--- Q. argentata Korth
--- Q. jenseniana Hand.-Mazz.
--- Q. augustinii Skan

Section 4 : Glauca Menits.
Leaves with small stellate hairs mixed with simple ones; leaves always dentate or nearly so, with at least 10 vein pairs; free styles 0.5-1.5 mm long; acorn ellipsoidal to half-round.
__ Sub-section 1. Lineatae Blume
Leaves with only simple hairs; acorn oblong; 14-20 vein pairs; cup conical with ringed peduncle.
--- Q. lineata Bl.
__ Sub-section 2. Lamellosae Menits.
Pubescence made of mixed simple and stellate hairs; acorn half-round or globose; veins strongly impressed adaxially, raised beneath; cup 2.5-5 cm in diameter, with broad, spreading rings.
--- Q. lamellosa Smith
--- Q. thomsoniana A.DC
__ Sub-section 3. Oxyodontes Menits.
As for sub-section Lamellosae, except veins slightly impressed above and strongly raised beneath; cup 1-3 cm in diameter, with narrow, appressed, denticulate rings.
--- Q. oxyodon Miq.
--- Q. lenticellata Barnett
--- Q. patelliformis Chun
--- Q. hilldebrandii (Hook.f.) A. Camus
--- Q. brevicalyx A. Camus
__ Sub-section 4. Glaucae Menits.
As for sub-section Lineatae, except 5-13 vein pairs; cup half-round, with peduncle not ringed.
--- Q. glauca Thunb. - ssp annulata (Smith) A. Camus - ssp glauca - ssp schottkyana (Rehd. et Wils.) Menits. - ssp longinux (Hayata) Menits.
--- Q. salicina Bl.
--- Q. myrsinifolia Bl.
--- Q. chevalieri Hick. et A.Camus
--- Q. djiringensis A.Camus
--- Q. rupestris Hick. et A.Camus
--- Q. bambusifolia Hance
--- Q. miyagii Koidz.

Section 5 : Helferiana Menits.
Leaves broadly elliptical to broadly lanceolate, crenate, dentate or less often sub-entire; leaves pubescent at first; acorn flattened, half-round or less often shortly cylindrical; style 0.5-1 mm long.
__ Sub-section 1. Helferianae Menits.
Cup much wider than high; 4-7 styles, stylopodium hairy except stigmas;
--- Q. rex Hemsley
--- Q. fructiseptata A.Camus
--- Q. helferiana A.DC
--- Q. kerrii Craib -
--- Q. austrocochinchinensis Hick. et A.Camus
--- Q. thorelii Hick. et A.Camus
--- Q. gomeziana A.Camus
--- Q. dussaudii Hick. et A.Camus
__ Sub-section 2. Subpedicellatae Menits.
Cup cylindrical or conical sometimes narrowed, with diameter that equals the height; hairs of stylopodium hiding the 3(-4) styles.
--- Q. brandisiana Kurz
--- Q. gaharuensis Soepadmo
--- Q. steenisii Soepadmo

Section 6 : Acuta Menits.
Mature leaves entire or dentate near apex, both sides hairless, young leaves pubescent; (3)4 styles 1-1.5 mm long; cup halfround, 1 cm in diameter, with narrow, yellowish pubescent rings, the lowest ones often crenate; acorn ellipsoidal, longer than wide, ripenning first year.
--- Q. acuta Thunb.
--- Q. morii Hayata
--- Q. nubium Hand.-Mazz.

Section 7 : Gilva Menits.
Stellate pubescence on the leaves and the narrow stylopodium; long, thick, simple hairs along veins; leaves conspicuously acute, always pubescent abaxially; 3(4) styles, sometimes connate; acorn ellipsoidal or cylindrical, as long as wide.
--- Q. lobbii Ettingsh.
--- Q. hunanensis Hand.-Mazz
--- Q. delavayi Franch.
--- Q. chungii Metcalf
--- Q. gilva Bl.

Section 8 : Lepidotricha Menits.
Mature leaves with stellate, intricate or partially connate trichomes, looking like scales; leaves small, entire or with 2-3 short teeth-pairs near apex; style free, less than 1 mm long; cup conical; acorn cylindrical shorter than wide, or globose.
--- Q. braianensis A. Camus
--- Q. hypophaea Hayata
--- Q. poilanei Hick. et A. Camus
--- Q. championii Benth.