Are insoles allowed in professional basketball?

For the most part, orthotics are allowed to be used by basketball players in professional leagues. For the most part, orthotics provide support and stability to the foot to help the player avoid injury while playing the sport and should not provide an athletic advantage to the player wearing them. There are some well known basketball players that do make use of orthotics in their shoe. However, if you are worried you can check with the professional governing body that regulates your sport to be sure.