Abstract: The present paper reviews the history of taxonomy of cycads in China, and reports a new Progress in investigation of resources of Chinese cycads. A revision of Cycas in China has been completed. A key to the cycads of China is presented as follows: 1. Leaves bipinnate or tripinnate; leaflets dichotomous. 2. Leaves 1, rarely 2 in an erect crown, tripinnate, 4-6m long; leaflets 3-5-dichotomously forked into abovate linear regular segments 7-12 cm long, caudate;ovules 8-10 (S. Yunnan: Honghe River) ........................ 1. C. multipinnata C. J. Chen & S. Y. Yang 2. Leaves 3- 5 in an erect to obliquely spreading sparse crown, bipinnate, 2- 3 (-4) m long; leaflets 1-2 (-3)-dichotomously forked into linear, irregular segments 10-25cm, acute to short acuminate; ovules often 4-6 (W. Guangxi: Longzhou, Ningming, Pingxiang) .............................................. 2. C. micholitzii Thiselton-Dyer 1. Leaves simply pinnate; leaflets simple. 3. Ovules densely tomentose, seeds often with remnant hairs. 4. Leaflets strongly revolute on margin; the upper sterile lamina narrow-ovate, margins deeply laciniate; seeds sclerotesta without grooves along sides (Fujian) ..................................................... ......................................... 4. C. revoluta Thunberg 4. Leaflets flat or slightly recurved on margin; the upper sterile lamina suborbicular or rhombic- orbicular, margins regularly pectinate; seeds sclerotesta with 2-3 irregularly grooves along each side (Taiwan: Taidong) .......................................... 5. C. taitungensis C. F. Shen, K. D. Hill, C. H. Tsou et C. J. Chem 3. Ovules and seeds glabrous. 5. Leaflets (12-)18-25mm wide, margins wavy; female cones loosely composed of 5-20 sporophylls (S. Yunnan, SW Guizhou, W. Guangxi) ............ 3. C. balansae Warburg (C. chevalieri Leandri, C. micholitzii var, simplicipinna Smitinand) 5. Leaflets 6-11 (-14)mm wide, margins entire; female cones tightly composed of more than 20 sporophylls. 6. Leaves 150-300 X 30-60 cm; midrib yellowish or greenyellowish, strongly elevated adaxially; terminal lobe of megasporophyll usually flattened, sometimes subulate. 7. Midrib strongly elevated on both surfaces when young and dry; seeds sclerotesta smooth (Nanpanjian Vellay in Guangxi, Guizhou and Yunnan) ...................... 8. C. szechuanensis Cheng & L. K. Fu (C. guizhouensis Lan et R. F. Zuo) 7. Midrib strongly elevated on both surfaces only when young, but nearly flat or slightly elevated abaxially when dry; seeds sclerotesta verrucose. 8. leaflets often less than 9 mm wide; mesophyll cells under the lower epidermis through over the midrib; petioles with denser spines at base; seeds 3. 5-4.5cm long (Hainan: Wanning, Lingshui, Baoting, Changjiang) ......................................6. C. hainanensis C. J. Chen ex Chang, L. K. Fu et C. Y. Cheng 8. Leaflets more than 10 mm wide, mesophyll cells under the lower epidermis stop before the midrib; petioles without spines or with remote spines at base; seeds 2.5-3.0 cm long Guangdong) ............................................................ 7. C. taiwaniana Carruthers 6. Leaves 50-130 X (12-)20-30(-40) mm; midrib greenish flat or slightly elevated adaxially; terminal lobe of megasporophyll sterile lamina subulate not flattened. 9. Trunk usually subterranean, swollen at base; bark white grey, smooth seed sarclotesta thin and tightly to woody sclerotesta layer. 10. Trunk to 1.5 m tall above ground; petioles with more than 10 spines on each side; median leaflets inserted at ca. 60°to rachis, base strongly constricted s seeds 3. 5-4. 0 X 3.0-3.5 cm (S. Yunnan, W. Guangxi) .......................... 9. C. siamemsis Miquel 10. Trunk often less than 25 cm tall above ground t petioles lacking spines or less than 8 spines on each side of upper part; median leaflets inserted at 90°to rachis, base truncate; seeds 2.0-2.8 X 1.8-2.5 cm (W. Guangxi) ........................................................... 10. C. miquelii Warburg 9. Trunk 1-7 m tall , cylindric; bark dark grey or brown; seeds shrunken, gradually de- teched and fragile when dry. 11. Trunk to 7 m tall , often forked apically, crown not heavily hairy; bark white grey, smooth; leaves green, keeled in cross-section at 50-60°to rachis; leaflet margins revolute or slightly recurved; midrib often sulcate adaxially when dry; seeds 4. 5-6.0 X 4.0-4.7cm (S. Yunnan) ....................................................................... 11. C. pectinata Hamilton ( C. jenkinsiana Griffith) 11. Trunk 1-2 (-3) m tall , simple, crown heavily hairy s bark dark brown, scaly s leaves blueish-green, nearly flat in cross-section; leaflet margins flat or somewhat recurred, midrib not sulcate; seeds 2.5-3.5 X 2. 2-3.0 cm (Jinsha River vellay between Sichuan and Yunnan) ............................12. C. panzhihuaensis L. Zhou et S. Y. Yang ( C. baguanheensis L. K, Fu et S. Z. Cheng)