Beedrill is a Pokémon which mostly resembles a bipedal, yellow wasp; however, it only has four legs instead of six and lacks pigment pits. Beedrill's head is round with a slightly pointed mouth, large, red eyes, and black antennae with a sharp bend in the middle. Its forelegs are tipped with long, conical stingers. It stands on its other two legs, which are long, segmented, and insectoid in shape. Beedrill has two pairs of rounded, veined wings, and another stinger on its yellow-and-black striped abdomen.
Beedrill is highly territorial and unlike real bees, Beedrill live in colonies rather than true "hives", and they work together to solve basic problems regarding food, territory and reproduction. As seen in the anime, Beedrill seems to be especially concerned with the welfare of Weedle and Kakuna and it will respond aggressively to those that disturb them. Disturbing one Beedrill will cause the whole colony to attack. It flies at high speed and attacks using the large venomous stingers on its forelegs and abdomen. The two stingers on its forelimbs allow it to use its former signature move, Twineedle. It will take the victims of its attacks back to its nest for food. Beedrill nests in temperate forests and misty wooded areas.
As Mega Beedrill, it gains more defined features. The antennae are shorter and T-shaped. Its eyes become longer and sleeker. It now has three pairs of wings; the uppermost pair is larger with a black trim along the top. Its stingers become longer and larger, resembling lances. Additional conical, black-and-yellow stingers with white tips take the place of its legs. Its abdomen becomes larger, grooved and is attached to its thorax by a black structure. A similar black structure connects its head and thorax. The stinger on its abdomen is now a pale yellow, and it now has black stripes over its entire body. Fast-acting poison is stored in the stingers on its limbs, while the tail stinger produces a slow-acting poison that is used to finish opponents. The instantaneous poisons are instead used to prevent the foe from fleeing.
In The Lost Lapras, a punk used a Beedrill to attack a Lapras. When Ash and Pikachu came to Lapras's defense, Beedrill battled Pikachu, only for it and its Trainer to flee after Tracey appeared, sketched them, and began comparing them in terms of how they were trained. According to Tracey, Beedrill's coloring was poor.
In Foggy Pokémon Orienteering!, Bonnie and Pikachu accidentally disturbed a Beedrill, the former of whom accidentally hit its head with a big twig. However, it quickly got away before Pikachu was about to attack it.
In The Electric Tale of Pikachu, Ashcaught a Beedrill in Kanto, and it was part of a swarm that he had disturbed when he caught a Mankey. He thought this Beedrill, along with Mankey, would help him to raise his Trainer level, but it couldn't.
Beedrill was in the first Super Smash Bros. game. When a Poké Ball was opened, one would come out and fly away. A few seconds later, a whole swarm would fly by and attack everyone on the field with Take Down except the user. Its role was taken over by Unown in Super Smash Bros. Melee.
Pokémon Super Mystery Dungeon: Two Beedrill and three female Combee act as bosses of Nectar Meadow, having misinterpreted Budew, the player, and the partner as honey thieves. One of the Beedrill also helps guard Revelation Mountain against intruders.
Beedrill's English name was originally going to be spelled Beedril.
Beedrill can be seen as a parallel to Butterfree. Both of their unevolved stages evolve into their respective first evolutionary stages at level 7, which then evolve into their respective final forms at level 10. They both also go through metamorphosis-like evolution and share a base stat total of 395. Also, while Beedrill is a version exclusive of Black and Black 2, Butterfree is exclusive to White and White 2.
In Pokémon Conquest, Beedrill is the only Pokémon that is featured without its evolutionary relatives.
Mega Beedrill has the highest Attack and Speed base stats of all Poison-type Pokémon. It also has the lowest Special Attack base stat of all Poison-type and Mega Evolved Pokémon, the lowest Defense of all Mega Evolved Pokémon, and the lowest single base stat of any Mega Evolved Pokémon.
Mega Beedrill is the only Mega Evolved Pokémon whose base Special Attack is lower than that of its base form.