Theekshana Ratnasekera (born 1 July 1982) is a Sri Lankan former swimmer, who specialized in sprint freestyle events.

[1] She represented Sri Lanka, as an 18-year-old teen, at the 2000 Summer Olympics, and also held numerous age group and meet records in a sprint freestyle (both 50 and 100 m).

Ratnasekera lost the race in the pre-Olympic selection to Radiesha Daluwatte, the teenage daughter of former Sri Lankan army commander Rohan Daluwatte, and the General filed a petition in the Court of Appeals to challenge the sports officials' decision to send Ratnasekera to the Olympics.

[4][5] Swimming in heat two, she held off a sprint battle against six other swimmers to overhaul a 30-second barrier and hit the wall first in a sterling time and a Sri Lankan record of 29.88.

This biographical article related to a Sri Lankan swimmer is a stub.