Dactylorhiza maculata reaches on average 15–45 centimetres (5.9–17.7 in) of height, with a maximum of 70 centimetres (28 in). These plants are bulbous geophytes, forming their buds in underground tubers or bulbs, organs that annually produce new stems, leaves and flowers. Furthermore, these orchids are "terrestrial", because unlike "epiphyte" species they do not live at the expense of other large plants. This orchid has an erect, glabrous and cylindrical stem, with a streaked surface. The leaves are oblong or oval-lanceolate, with dark ellipsoid-shaped "spots" on the surface (hence the species name). The leaves are amplexicaul and can be either radical (basal) or cauline.
The underground part of the stem has two webbed tubers each one more or less deeply divided into several lobes or tubercles (characteristic of the genus Dactylorhiza), the first one plays the important functions of supplying the stem, while the second one collects nutrient materials for the development of the plant that will form in the coming year. The inflorescence is 5–15 centimetres (2.0–5.9 in) long and it is composed of flowers gathered in dense spikes. The flowers are placed in the axils of bracts membranous and lanceolate-shaped. Their colors vary from light pink to purple or white with darker streaks mainly on the labellum (sometimes at the margins of tepals). The flowers reaches on average 10–15 centimetres (3.9–5.9 in). The flowers are hermaphrodite and pollinated by insects, especially bumblebees. However the seeds germination is conditioned by the presence of specific fungi.