Provided is a beverage which has a stable colour tone and flavour, even if stored in a heated state, or stored for a long period. The packaged green tea beverage contains ascorbic acid at a concentration of 100-800 ppm, and valine at a concentration of 1-200 ppm. The degree of brightness (L*) and the degree of colour saturation (C*) of the beverage, which are measured by a colour difference meter, satisfy the following: (i) 75≤L*≤95 (ii) 15≤C*≤25