The 21-year-old midfielder appeared to make the provocative signal towards the home fans following Swansea's 1-0 Premier League defeat at the Cardiff City Stadium last weekend, but he has escaped with a warning.
The 'swim away' gesture came as the midfielder made his way towards the Swansea supporters after the final whistle on Sunday, and is believed to be in reference to an incident in 1988 when Cardiff fans were allegedly forced into the sea as they clashed with their Swansea counterparts.
The Football Association have warned Shelvey about his future conduct, but confirmed that he will not be punished.
A statement read: "Following an investigation, the FA has reminded Jonjo Shelvey of his responsibilities. No further action will follow."
Shelvey has not travelled with Swansea for their UEFA Europa League clash with Kuban Krasnodar due to family reasons, but is expected to face Stoke on Sunday.
