The rotation curve of galaxy is a graph of the rotational velocity of stars, gas and other bodies orbiting around the center of galaxy and their radial distance from the centre of galaxy. The orbital speeds of stars, gas and other bodies contained in the galaxy do not obey the rules found in the other orbital systems. Stars are orbiting around their galaxy's centre at equal or increasing speed over a large range of distances. In contrast, the orbital velocities of planets in solar system and moons orbiting around the planets decrease with distance. The galaxy rotation problem is the discrepancy between observed galaxy rotation curve and theoretical prediction based on the observed luminous or baryonic material or bodies. When mass profiles of galaxies are calculated from the distribution of stars and mass- to- light ratios in stellar disk, they do not match with the masses derived from the observed rotation curve and law of gravity. None of the existing theories including Newtonian gravity and general relativity can explain the Galaxy rotation curve correctly. The rotation curve of galaxies will be explained by using new quantum gravity developed by me.