The woman came off her jet-ski when she hit a wave off the shore at Lee-on-the-Solent.
Gosport and Fareham Inshore Rescue Service pulled her into their boat and gave her oxygen.
She was then taken to the shore where she was checked over by paramedics, before being taken to Queen Alexandra Hospital.
Audrey Pedersen, coastguard watch assistant, said: 'She was brought in shore very slowly so that she wasn't caused too much discomfort and then taken to hospital.'
It was later confirmed that the woman had broken her femur.
The coastguard received the call at 3.46pm and she was on the way to hospital by 4.20pm.
The rescue service also had to tow in two jet-skiers yesterday after they broke down.
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