The hydrolytic instability of fluorescent powder can diminish luminescent concrete’s mechanical strength and luminescent performance. This study used two methods, SiO2 coating and hydrophobic treatment, to treat long afterglow fluorescent powder with water resistance and prepare luminescent concrete. The compressive strength, luminescent performance and microstructure of luminescent concrete prepared by adding fluorescent powder with different water resistance treatments were tested to reveal the mechanism of improving the performance of luminescent concrete by fluorescent powder. The results show that, compared to the SiO2 encapsulation method, the hydrophobic treatment of fluorescent powder achieves superior water resistance performance. And the 28 d compressive strength of hydrophobic treated fluorescent powder luminescent concrete has increased by 8.0%~25.7%, with a maximum strength of 80.2 MPa and an optimal dosage of 5%~10% (mass fraction). Excessive addition will have adverse effects. Compared with the luminescent concrete without water-resistant fluorescent powder, the microstructure density, compressive strength and luminescent performance of the two types of water-resistant fluorescent powder luminescent concrete are significantly improved.