The keystone design perforator island flap can be utilized in the repair of trunk defects. A systematic review was carried out to identify the complication rates of the use of this flap to treat such defects. The MEDLINE, Embase, Cochrane Library, and PubMed Central databases were searched for articles published between January 2003 and December 2018 that reported the use of keystone design perforator island flaps in the repair of trunk defects. Study selection was conducted in alignment with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. Eight articles involving a total of 54 flaps satisfied the inclusion criteria. The most frequently reported cause of trunk defects was oncologic resection (64.4%). The overall complication rate was 35.2%, and complications included infection (11.1%), wound dehiscence (7.4%), delayed healing (7.4%), and partial flap loss (1.9%). The keystone design perforator island flap is associated with a high success rate and low technical complexity. Despite minor complications, keystone design flaps could be a preferred choice for trunk reconstruction.