Eu2+ and Dy3+ co-doped alkaline earth silicate fluorescent powders are synthesized by the high temperature solid-phase method and the microwave combustion method. The properties of the fluorescent powders are analyzed and measured by scanning electron microscope, X-ray diffractometer and fluorescence analyser. The results show that the Ba5Si8O21∶Eu2+, Dy3+ fluorescent powders synthesized by the high temperature solid-phase method have the best fluorescence property when they are sintered at 1150 ℃ and the Eu2+/Dy3+ ratio (the ratio of mole fraction) is 1∶3. Comparing the high temperature solid-phase method with the microwave combustion method, it is found that the microwave combustion method can reduce the synthesis time of Ba5Si8O21∶Eu2+, Dy3+ significantly, but the luminescent intensity of products is low. Comparing the properties of the synthesized Sr2MgSi2O7∶Eu2+, Dy3+ with those of Ba5Si8O21∶Eu2+, Dy3+, it is found that the type of alkaline earth metal ions has an effect on the emission wavelength of fluorescent powders. Ba5Si8O21∶Eu2+, Dy3+ fluorescent powders have good water resistance, and their fluorescence loss rate is only 2.3% after 24-h water immersion, which can be applied to fluorescent coatings.