The panther chameleon (Furcifer pardalis) is a species of chameleon found in the eastern and northern parts of Madagascar in a tropical forest biome. Additionally, it has been introduced to Réunion and Mauritius, as well as the state of Florida within the United States.

The panther chameleon was first described by French naturalist Georges Cuvier in 1829. Its generic name (Furcifer) is derived from the Latin root furci meaning "forked" and refers to the shape of the animal's feet. The specific name pardalis refers to the animals' markings, as it is Latin for "leopard" or "spotted like a panther". The English word chameleon (also chamaeleon) derives from Latin chamaeleō, a borrowing of the Ancient Greek χαμαιλέων (khamailéōn), a compound of χαμαί (khamaí) "on the ground" and λέων (léōn) "lion". The Greek word is a calque translating the Akkadian nēš qaqqari, "ground lion". This lends to the common English name of "panther chameleon".

Although currently regarded as a single widespread and variably-colored species, evidence from genetics and captive breeding indicates that it possibly should be split into several different species.

Panther chameleons grow 16-20" (40–51 cm) long, with females typically being smaller than males. In a form of sexual dimorphism, males are more vibrantly colored than the females. Another form of sexual dimorphism is in size, it has been concluded that males are much larger and heavier than females and therefore seen as a large sex difference in body size. Coloration varies with location, and the different color patterns of panther chameleons are commonly referred to as 'locales', which are named after the geographical location in which they are found. Panther chameleons from the areas of Nosy Be, Ankify, and Ambanja are typically a vibrant blue, and those from Ambilobe, Antsiranana, and Sambava are red, green or orange. The areas of Maroantsetra and Tamatave yield primarily red specimens. Numerous other color phases and patterns occur between and within regions. Females generally remain tan and brown with hints of pink, peach, or bright orange, no matter where they are found, but there are slight differences in patterns and colors among the different color phases.

Like all chameleons, panther chameleons exhibit a specialized arrangement of toes. On each foot, the five toes are fused into a group of two and a group of three; these specialized feet allow the panther chameleon a tight grip on narrow branches. Each toe is equipped with a sharp claw to gain traction on surfaces such as bark when climbing. On the forelimbs, there are two toes on the outer (distal) side of each foot and three on the inside (medial). On the hind legs, the arrangement is reversed: two toes are fused medially and three distally.

Panther chameleons have very long tongues (sometimes longer than their own body length) which they are capable of rapidly extending out of the mouth to capture prey, which is mostly terrestrial invertebrates and very rarely, plant material. Once the tip sticks to a prey item, it is drawn quickly back into the mouth, where the panther chameleon's strong jaws crush it and it is consumed.

Panther chameleons are native to Madagascar; this species is widespread in lowland areas of the eastern and northeastern sections of the country. Additionally, it has been introduced to Réunion and Mauritius and recently within the US state of Florida through the pet trade.

The panther chameleon lives in regions of rainforest in the east and drier broken forest/savannah in the northwest. The original primary plant communities within their range has been degraded by human activity; panther chameleons appear to thrive in degraded habitat and are frequently found near roads, homes, and in plantations.