Energy transfers and upconversion fluorescence spectroscopy in both Er3＋ singly doped and Tm3＋-Yb3＋ co-doped AlF3-based flouride glass,excited at 970nm,are investigated experimentally.In Er3＋:AYF glass,the optium Er3＋content for 550nm emission is about at 6mol%,which is 12mol% in AZF glass.With the increase of Er3＋ content,the intensity ratio of the red emission to the green emission (Ired/Igreen) is increased in AYF and AZF glass,and the red emission intensity in these gass depends on (Ｐex)1.6.They are mainly due to a cross-relaxation process between two erbium ions,one in the 4Ｓ3/2 and the other in the 4Ｉ9/2.In Tm3＋-Yb3＋ co-doped AlF3-based flouride glass,the concentration quenching of Tm3＋ in blue at 476nm is stronger than that in infrared light at 793nm,and the optimum content of Tm3＋ for 476nm emission is about 0.1mol%,while it is (0.3—5)mol% for 793nm emission.The concentration quenching of Yb3＋ to upconvertion fluorescence is also observed.It may be due to the back-energy transfer from the 3Ｆ4 level of Tm3＋ to the 2Ｆ5/2 level of Yb3＋.