Ewan had endured a difficult Grand Tour in Italy, crashing on the opening day, finishing eighth in Stage 3, and crossing the line more than half an hour behind winner Biniam Girmay (Intermarche-Wanty-Gobert Materiaux) in Stage 10.
A narrow defeat to Arnaud Demare (Groupama-FDJ) was the closest the Lotto Soudal star got to a stage win through the first 11 stages, and the Belgian team have since confirmed his decision.
"Caleb Ewan will not be at the start of stage twelve of the Giro," Lotto Soudal announced on Twitter.
"As initially planned, the Australian will leave the Giro during the second week of racing.
"With plenty of mountain stages coming up, together with the team it was decided that Ewan will be heading home."
The Australian hinted he would not contest the rest of the Giro in a recent interview on the second rest day, though he would have expected at least one stage win under his belt.
Nevertheless, the 27-year-old will now shift his focus to the Tour de France, with the Baloise Belgium Tour in June reportedly part of his preparations.
SBS and SBS On Demand will broadcast every stage of the Tour de France from July 1-24, and a fully-fit Ewan will no doubt be among the sprinters to beat.