The Pole won last year's China Open after beating Russian Liudmila Samsonova in straight sets in the final.
Swiatek withdrew from the Canadian Open and Korea Open citing fatigue having won the French Open title in June and a bronze medal at the Paris 2024 Olympics before losing to American Jessica Pegula in the US Open quarter-finals.
"Due to personal matters, I'm forced to withdraw from the China Open in Beijing," Swiatek said in a statement.
"I'm very sorry as I had an amazing time playing and winning this tournament last year and was really looking forward to being back there.
"I know that the fans will experience great tennis there and I'm sorry I won't be a part of it this time."
The WTA 1000 event will run from September 25th to October 6th.