Pilar Shimizu (born May 27, 1996 in Tamuning, Guam) is a Guamanian breaststroke swimmer.

While qualifying for the 2012 Summer Olympics she broke the 20-year-old national record set by Tammie Kaae, another Olympian from Guam.

[8] Shimizu established the national record for the 100 meter breaststroke (set 20 years prior by Tammie Kaee) during the Games, with a time of 1:15.76.

[5] After swimming for Johns Hopkins for two years, Shimizu decided to train with a private club that would better prepare her for the Olympics.

[7] Shimizu competed in the 100 meter breaststroke during the 2016 Summer Olympics in Rio, with the goal of setting a personal and national record.

Her first international success came in 2010, when she won the first medal for Guam at the Oceania Swimming Championships, a bronze in the 100 meter at the age of 14.

[14] Adeline Williams won the 100 meter breaststroke with a Pacific Games record time of 1:11.05.