The Chinese national charged with trespassing at Mar-a-Lago acted “weird and strange” from the moment she set foot in President Trump’s South Florida retreat, wearing an evening gown in the middle of the day, a receptionist testified Tuesday.

“As soon as she entered the lobby, you could see that she was fascinated, she was looking around,” said Ariela Grumaz of Yujing Zhang, now in the second day of her trial at Fort Lauderdale federal court, according to NBC affiliate WPTV.

Zhang — clad in an evening dress despite it being 1 p.m. — stared wide-eyed at the ornate trappings and shot photos and videos on her phone, which members would know is in violation of club rules, Grumaz testified of the March incident.

When Zhang, 33, said that she was there for a “UN Chinese” function, Grumaz stepped away to ask a catering manager if the event was even on the agenda — but not before asking a Secret Service agent to keep an eye on Zhang, according to WPTV.

By the time she returned, Grumaz found agents gathered around a bathroom door waiting for Zhang to emerge.

“There’s a hallway, and I could see her texting, walking back and forth, on the phone,” testified Grumaz, according to WPTV. “I called [Zhang] and I said, ‘Ma’am, can you please step outside?’ She looked at me.

“That’s what shocked me. She had a blank face. She was totally in control.”

Zhang was ultimately found to be carrying a trove of spy gear, including a device capable of detecting cameras and a thumb drive loaded with what was initially believed to be malware, though prosecutors have elected not to charge her with espionage.

Much to the consternation of Judge Roy Altman, Zhang insisted upon representing herself in the bizarre trial, which included a delay Monday when Zhang groused that she didn’t have any underwear.

Zhang faces up to six years behind bars if convicted.

With Post Wires