Abstract: The diurnal variations of photosynthetic rate (Pn), stomatal conductance (Cond), transpiration rate (Tr), intercellular CO₂ concentration (Ci), water using efficiency (WUE), solar radiation (PAR) of Miscanthus sinensis ‘Strictus’, Panicum virgatum ‘Rehbraun’, Phalaris arundinacea ‘Picta’, M. sinensis ‘Cabaret’, Cortaderia selloana ‘Pumila’, M. sinensis ‘Cosmopolitan’ and M. sinensis ‘Morning light’ were determined by Li-6400 portable photosynthetic system, and the light saturation point (LSP) and the light compensation point (LCP) were calculated at the same time. Among the 7 ornamental grasses, the LSP,Pn and WUE of P. virgatum ‘Rehbraun’ were the highest. Both M. sinensis ‘Morning light’ and P. arundinacea ‘Picta’ have higher Cond,the Pn and Tr of M. sinensis ‘Morning light’ were the higher and P. arundinacea ‘Picta’ was the lower. WUE of P. arundinacea ‘Picta’ was lowest with low dry tolerance and good performance at wet site which was a shade tolerance plant of C₃ plant characters with appearing noon-rest phenomenon dued to the decrease of Cond. Shade tolerance from strong to weak were ranked as follows: C. selloana ‘Pumila’＞P. arundinacea ‘Picta’＞M. sinensis ‘Cabaret’＞M. sinensis ‘Cosmopolitan’＞ M. sinensis ‘Strictus’＞P. virgatum ‘Rehbraun’＞M. sinensis ‘Morning light’.