Tsuna is set to become the tenth generation boss of the Vongola family.
In school, Tsuna has been given the harsh nickname of "No Good Tsuna", as he is very clumsy, gets low marks in school and is somewhat of a pushover.
Although he is the tenth generation Vongola boss, Tsuna is unwilling to take part in anything that has to do with the Mafia. He always denies the fact that he is a future Mafia boss and tries to avoid anyone involved with the Mafia. In the Future arc he states that he would rather destroy the Vongola family than accept its bloody history. Tsuna is often surprised and horrified (for a comedic effect) at Reborn's and other mafiosos' actions. Later, even though he still wants nothing to do with the Mafia, he is grateful for the friends he has made since meeting Reborn. He cares a lot for his new 'family' and would put himself in the way of danger in order to protect them.
There have been many parallels that link Tsuna with the first boss and founder of the Vongola family, Giotto. Both of their personalities are likely to be very similar as it has been shown that they have similar goals and ways of standards.