A new luminescence material-LaPO

4

doped with Eu

2+

and Ce

3+

was prepared by high temperature solid state reaction. And the optical properties of Eu

2+

activated and Ce

3+

Eu

2+

coactivated lanthanum phosphates were investigated by using photoluminescence(PL) measurements. Emission spectrum of LaPO

4

:Eu

2+

recorded at room temperature with 324nm excitation shows a broad emission band centered at 423nm.And it is possible to determine the distribution of this broad emission band in the spectrum associated with transition from the 4f5d level of Eu

2+

ion. The excitation spectrum of Eu

2+

activated lanthanum phosphate recorded at room temperature monitoring 423nm emission exhibits absorption in UV region (220～400nm) assigned to the 4f→5d transition of Eu

2+

ion. Lanthanum phosphate doped with Ce

3+

was also prepared by high temperature solid state reaction. The room temperature photoluminescence spectra of LaPO

4

:Ce

3+

show the broad emission and excitation band of Ce

3+

ion

around 342nm and 284nm

respectively. From these spectra above

it's possible to deduce that energy transfer between the Eu

2+

and Ce

3+

ion will probably happen because of the well overlapping between Ce

3+

emission and Eu

2+

excitation. And it's well proved in the excitation spectrum of LaPO

4

coactivated by Eu

2+

and Ce

3+

at room temperature

monitoring Eu

2+

emission. This spectrum shows a strong absorption band of Ce

3+

ranging over 220～340nm

in addition to original f→d transition of Eu

2+

(220～400nm). That is to say there happens a sensitization of Eu

2+

by the presence of Ce

3+

ion. The Eu

2+

emission intensity of LaPO

4

:Ce

0.01

3+

Eu

0.01

2+

is 5.6 times higher than that of the corresponding phosphor activated by Eu

2+

only. A series of LaPO

4

:Ce

0.01

3+

Eu

x

2+

were prepared to study the mechanism of the energy transfer between the Eu

2+

and Ce

3+

ion. The emission spectra of the LaPO

4

:Ce

0.01

3+

Eu

x

2+

at room temperature were measured. The relationship between the Ce

3+

donor emission intensity and the Eu

2+

acceptor concentration was fit to the d→d (dipole dipole) energy transfer model for multipole multipole interaction. So it is concluded that the energy transfer between the Ce

3+

and Eu

2+

ions in lanthanum phosphate is to be a process of dipole dipole resonance interaction.