Peter Lescouhier’s wife Xiang Xueqiu was shopping in Seoul earlier this month when she was followed out of a store by an assistant, who wanted to check her bag for stolen clothes.
CCTV footage shows Ms Xueqiu returning to the store and confronting the worker, apparently angered.
When another employee tried to intervene, Ms Xueqiu shoved her and then slapped her.
She has since been hospitalised after suffering a stroke last week. The Belgian embassy issued a statement addressing the incident.
“The Ambassador of Belgium sincerely regrets the incident involving his wife which happened on April 9 and wants to apologise on her behalf,” the embassy posted on Facebook.
“No matter the circumstances, the way she reacted is unacceptable.”
Police are currently investigating the incident.
The embassy said Ms Xueqiu would speak to them as soon as possible.
“We hope her health will improve quickly, so she will soon be able to assist with the police investigation, so we can all put this regrettable incident behind us,” the statement read.