Cuscuta sandwichiana is a parasitic vine that can be annual or perennial, characterized by its twining growth form that attaches to hosts through haustoria, effectively making it appear leafless and rootless. It lacks chlorophyll or has very little, relying on its host for nutrition. The stems of this vine are slender, ranging in color from yellow to yellowish orange, and are filiform in juvenile plants. Initially, these plants may have a small root system, which quickly degenerates, leading to mature plants not connected to the ground and exhibiting simple pubescent hairs. The leaves are significantly reduced, appearing scale-like, and alternate along the stem, with absent stipules. Its flowers are arranged in compact, short-pedicellate, cymose clusters, often with a glandular pubescence. These bisexual (perfect) flowers are actinomorphic and typically 5-merous, with a calyx composed of (3)4–5 sepals that can be distinct or connate at the base, enclosing the corolla nearly to its apex. The corolla is fused, urceolate, campanulate, or cylindrical, with white or pink lobes that are imbricate and exhibit various fringed or cleft scales below the stamens. Fruit development results in circumscissile or irregularly dehiscent capsules, sometimes indehiscent and fleshy, with a globose to depressed-globose shape approximately 3–3.5 mm in diameter, surrounded by the withered corolla. It produces 1–4 smooth or roughened seeds, dark reddish brown, and nearly without cotyledons, within a starchy endosperm; ca. 2 mm long. It is found scattered to locally common in coastal areas, often in sandy soil, without being host-specific. Its elevation range spans from 0-300 meters.