Jessica Evelyn Pengelly (born 1 July 1991) is a South African-born Australian swimmer, who specializes in freestyle and individual medley events.

[2] A 2008 Olympian, she has claimed multiple South African championship titles and national records in the individual medley (both 200 and 400 m), and won a total of five medals (three silver and two bronze) at the 2007 All-Africa Games in Algiers, Algeria.

[3][4] Pengelly also set two South African records in the freestyle relays at the 2008 FINA World Short Course Championships in Manchester, England, and at the 2011 Summer Universiade in Shenzhen, China.

[3][6] On the first night of the Games, Pengelly held off the fast-charging French swimmer Joanne Andraca to save the seventh spot and twenty-first overall by 2.84 seconds in heat five of the 400 m individual medley, finishing with a time of 4:41.04.

[7] Two days later, in the 200 m individual medley, Pengelly scored a time of 2:15.80 to touch out the daunting Dutch swimmer Femke Heemskerk by almost a quarter of her body-length for the fifth spot in heat two, but missed the semifinals with a twenty-sixth-place finish from the prelims.