Heavy-metal fluoride glasses have attracted much attention as host materials due to smaller multi-phonon relaxation rate and high transparence. The optical properties of Pr

3+

ion doped in hosts have also been investigated extensively for its potential application on full-color displays

optical data storage and biomedical instruments. Since detailed spectroscopic studies provide information leading to an assessment of the application of Pr

3+

ions

it is very urgent to explore the optical properties of different levels of Pr

3+

ions in different host materials. The purpose of this paper is to investigate optical characteristics of the

3

P

0

and

1

D

2

levels in Pr

3+

:ZBLAN fluoride glass. Firstly the absorption spectra of Pr

3+

:ZBLAN with two concentrations (110

-3

and 510

-3

in mass fraction were measured by using a spectrophotometer. Then by using time-resolved laser spectroscopy technique

the fluorescence spectra and the lifetimes of the

3

P

0

and

1

D

2

excited states of Pr

3+

ions were investigated under one-photon resonant excitation by a laser beam from the optical parameter oscillator and amplifier system. Experimental fluorescence intensities of the different emission bands were compared with the calculated radiative rates by the Judd-Ofelt theory in literature which indicating that the phenomenological intensity parameters for the Judd-Ofelt theory obtained for Pr

3+

:ZBLAN is reliable. Due to the concentration quenching

the fluorescent intensity of the 110

-3

sample is stronger than that of the 510

-3

sample. However

the lifetimes of the

3

P

0

and

1

D

2

excited states of Pr

3+

ions in ZBLAN glass are not influenced by the concentration. For 110

-3

sample

the measured lifetimes of the

3

P

0

and

1

D

2

(levels) are 46 and 322 s

respectively.