The NHS Trust responsible for the site in the Northgate car park said it had ongoing issues with power.
It has close for the rest of the day but is due to reopen at 10.30am tomorrow.
A spokesperson for Sussex Community NHS Foundation Trust said: “Due to an issue with the power supply we took the difficult decision to temporarily close our vaccination centre at Northgate, Chichester.
We have contacted people with booked appointments to let them know about the closure and our staff have been on hand at the centre and in the car park to offer help and answer any questions.
“We would like to thank everyone for their support and patience today and apologise for any inconvenience that the temporary closure has caused. The centre will reopen on Friday 8 October at 10.30am for both booked appointments and walk in vaccinations.”
In a message on Twitter, Sussex Community NHS Foundation Trust said: "Due to ongoing issues with the power at our Chichester vaccination centre at Northgate we have decided to close for the rest of the day.
"Anyone with an appointment is being contacted. We will reopen at 10.30am tomorrow (Friday October 8). Thank you for your understanding."