A retracting tip trocar assembly including a trocar tube and a shaft having a piercing tip at one end thereof. The device includes a retracting mechanism which allows the piercing tip to be held in a cutting position upon application of an insertion force such as when the piercing tip is pressed against a wall of a human body cavity. Upon release of the insertion force, such as when the piercing tip passes through the wall, the retracting mechanism causes the piercing tip to be retracted into the trocar tube.