Aguero played just five times for his new club after joining from Manchester City this summer and scored one goal which was a consolation in a 2-1 defeat to Real Madrid in October.
The former Atletico Madrid striker's final game came against Deportivo Alaves on October 30, when he was substituted on the cusp of halftime with chest complaints.
He was initially ruled out for three months but one of the most prolific strikers in the 21st century will not be returning to the field.
Before joining Barcelona, Aguero earned cult hero status in a ten-year spell with Man City, where he became the club's all-time top scorer with 260 goals in 390 appearances.
He won five Premier League titles with the Citizens, one FA Cup and six League Cups.
In an emotional farewell speech at the Camp Nou, Aguero said: "This conference is to announce I have decided to stop playing professional football."
"It is a very difficult moment. The decision I have taken is for my health [and relates to] the problem I had a month-and-a-half ago. I have been in good hands with the medical staff.
"I made the decision 10 days ago after doing everything possible to have some hope of playing on. I am very proud of my career. I always dreamed of a professional career since the first time I touched a ball at five.
"I want to thank Atletico Madrid who took a chance on me when I was 18 and Manchester City, everyone knows how I feel about City and how well they treated me there.
"I will leave with my head held high. I don't know what awaits me in the next part of my life. But I know I have people who love me. I will always remember the amazing things."
Aguero won 101 caps for Argentina, scoring 41 goals and helped them win the Copa America this summer.
