Astelia waialealae is a short, rhizomatous perennial herb in the Asteliaceae family. It has silvery leaves that are 12 to 20 cm (4.7 to 7.9 in) long and 1.3 to 2.2 cm (0.5 to 0.9 in) wide, with scales present on both surfaces. The staminate flowers are in racemes 3.0 to 7.0 cm (1.2 to 2.8 in) long and the tepals (outer part of a flower, which includes the petals or sepals) are dark purple. The pistillate flowers are also in racemes, which are 2.5 to 3.0 cm (1.0 to 1.2 in) long and have dark purple tepals. It has berries that are orange, ovoid, 8.0 mm (0.3 in) long and 4 mm (0.2 in) in diameter.