A direct counting method was used to investigate the feeding intensity, feeding rhythms, and food selectivity to Chlorella pyernoidesa, Chaetoceros muelleri, Isochrysis zhanjiangensis, Platymonas subcordiformis, Dunaliella salina, Nitzschiella closterium of Daphniopsis tibetana maintained under different temperature, salinity and food. The results showed that the filtration rate and grazing rate of D. tibetana increased with the increase of temperature in range of 2-20℃, and reached highest values at 14-16℃. The highest grazing rates, 1.88 and 3.46 ngC/(ind?h) were obtained for the larvae and adults, respectively, fed on I. zhanjiangensis at the salinity of 20. The filtration rate and grazing rate of D. tibetama fed on C. muelleri increased with the increase of instar, while opposite trend existed for those fed on I. zhanjiangensis. The ration of D. tibetama fed both on C. muelleri and I. zhanjiangensis decreased with the increase of body length. The filtration rate and grazing rate of larvae and adults showed similar trends which changed with food concentration; Both larvae and adults fed on D. salina with the concentration of 1×106 ind./L had the highest filtration rate and grazing rate, i.e. 0194,0.221 mL/(ind?h) and 0.030, 0.034 gC/(ind?h), respectively. The food selectivity of larvae to six species of algae were C. muelleri >C. pyrenoidesa> D. salina> P. subcordiformis>I. zhanjiangensis > N. closterium, while that of adults were P. subcordiformis> C. muelleri>D. salina>I. zhanjiangensis >C. pyrenidesa > N. closterium. For both larvae and adults, food selectivity to C. muelleri and D. salina had better.than that to the other micro algae. Similar feeding rhythms existed in larval and adult D. tibetama fed on C. muelleri, of which there were two high feeding peaks at 15:00-17:00 and 01:00-03:00, as well as two low feeding valleys at 09:00-11:00 and 23:00-01:00.