An alkaline earth aluminate phosphor for a cold cathode fluorescent lamp, which is represented by the compositional formula a (P.sub.1-xEu.sub.x)O.(Q.sub.1-yMn.sub.y)O.bAl.sub.2O.sub.3 and which is characterized by emitting light when irradiated with ultraviolet rays having a wavelength of from 180 to 300 nm (provided that in the above formula, P represents at least one alkaline earth metal element selected from Ba, Sr and Ca, Q represents at least one bivalent metal element selected from Mg and Zn, and a, b, x and y represent numbers which satisfy 0.8.ltoreq.a.ltoreq.1.2, 4.5.ltoreq.b.ltoreq.5.5, 0.05.ltoreq.x.ltoreq.0.25 and 0.2.ltoreq.y.ltoreq.0.4, respectively).