Based on potted natural drought method,the study discussed the response mechanisms of plant chlorophyll fluorescence parameters on drought stress with P.pungentisepala,P.yungfuensis,P.‘Flying Wings’and P.‘Venus’ as materials.The results showed that with the extension of drought time,the minimal fluorescence(Fo) of P.pungentisepala was decreased significantly on 30 d after drought stress,while those of the other three kinds varied insignificantly.The maximal fluorescence(Fm) of P.pungentisepal,P.‘Flying Wings’ and P.‘Venus’ were not obvious compared with 0 d,and that of P.yungfuensis was significantly lower than 0 d on 45 d after drought stress.The maximum photochemical efficiency(Fv/Fm)basically showed a trend of first increasing and then decreasing,P.pungentisepala increased significantly on 30 d after drought stress,and P.‘Flying Wings’ increased significantly on 15 d after drought stress,P.‘Venus’ significantly decreased on 45 d after drought stress.The electron transport rate(ETR) mainly decreased first,then increased,and then decreased again,P.yungfuensis,P.‘Flying Wings’and P.‘Venus’all decreased significantly on 15 d and 45 d after drought stress,and yet P.pungentisepala decreased significantly on 15 d and 30 d after drought stress.The non-photochemical quenching(NPQ) showed a trend of first increasing and then decreasing or a trend of first increasing and then decreasing and yet rising,P.pungentisepala rose signifiantly on 15 d and 30 d after drought stress,yet decreased on 45 d after drought stress,P.yungfuensis significantly increased in different drought periods,P.‘Flying Wings’ and P.‘Venus’ significantly increased on 15 d and 45 d after drought stress.The photochemical quenching(qP) changes of P.pungentisepala and P.yungfuensis were not significant in different drought periods,whereas P.‘Flying Wings’ and P.‘Venus’ first decreased,then increased and then decreased.