Sr2SiO4:xEu^2+ phosphors were synthesized through the solid-state reaction technique. The crystal phase of Sr2SiO4:xEu^2+ phosphor manipulated by Eu^2+ concentration was studied. The phase transited from β to α' in Sr2SiO4:xEu^2+ phosphor with increasing europium concentration. The single β phase was formed as x≤005 and changed α' phase when x〉0.01. The emission spectrum of the β-Sr2SiO4:Eu^2+ phosphor consisted of a green-yellow broadband peaking at around 540 nm and a blue band at 470 nm under near ultraviolet excitation. The white LEDs by combining near ultraviolet chips with β-Sr2SiO4:Eu^2+ phosphors were fabricated. The luminous efficiency (15.7lm/W) was higher than α'-Sr2SiO4:Eu^2+ phosphor white LED.