It was the first sighting of He since the conference in Hong Kong.
He has been living in a fourth-floor apartment at the guesthouse, which is located on the Southern University of Science and Technology campus, The Times reported.
The scientist could be seen speaking with a woman who was carrying a baby, according to The Times. She appeared to be his wife.
Hotel staff confirmed to The Times that He was staying in the apartment, but The Times did not know if the guards had an affiliation with police or university officials. They did not identify themselves.
Chen Peng, a co-founder of the gene-testing company Vienomics, told The Times that he had spoken to He after the summit.
"He is safe," Chen told The Times. "But I don’t know his exact whereabouts or what state he is in."