Ca2-xSrxZn4Ti15O36∶Pr red long decay phosphor was synthesized by high temperature solid state reaction. Photoluminescence property and crystalline and unit cell parameters of the orthorhombic were investigated by fluorescence spectrophotometer and by powder X-ray diffraction, respectively. The emission intensity at 618 nm changes sharply when the concentration of Sr2+ (x) is less than 0.1 and the emission intensity reaches the maximum when x is equal to 0.007. There is an obviously broad excitation band at 270 nm when x is equal to 0.003 and it disappears gradually when x is over 0.01. The unit cell a parameter of Ca2-xSrxZn4Ti15O36∶Pr decreases while c parameter increases with the increases of the concentration of the doped Sr2+. When x is over 0.1 the value of the unit cell parameters a and c become stable. TL peaks of Ca2Zn4Ti15O36∶Pr, Ca1.993Sr0.007Zn4Ti15O36∶0.002Pr3+, 0.002Na+, are located at 62 ℃, 88 ℃, respectively, which indicates that there are deeper traps in Ca1.993Sr0.007Zn4 Ti15O36∶0.002Pr3+, 0.002Na+.