To qualify for PIP, you need to be aged between 16 and state pension age. At the moment, the state pension age for both men and women is 66. However, this will be rising to 67 gradually between 2016 to 2028.
The state pension age will rise further from 67 to 68 and this will happen gradually from 2044-2046. People born after 6th April 1978 will reach state pension age on their 68th birthday.
You can check the age at which you will personally reach state pension age here: https://www.gov.uk/state-pension-age
