State news agency KCNA mentioned his new role in its reporting on activities of North Korean leader Kim Jong-un.
Several high-ranking officials have been purged under Mr Kim, but Ri Yong-gil’s removal is unconfirmed.
However, senior officials in North Korea have previously been absent from view for long periods only to reappear.
South Korean media reported on 10 February that Gen Ri had been executed earlier this month for corruption and “factional conspiracy”.
Rumours that Gen Ri had fallen from favour first surfaced late last year. Gen Ri Myong-su had also appeared at a recent rally in Pyongyang and been mentioned in the slot normally reserved for the chief of staff.
Yesterday, KCNA mentioned Gen Ri Myong-su twice – once describing him as “chief of the Korean People’s Army (KPA) General Staff” whilst reporting on Mr Kim’s observation of aerial manoeuvres, and again when accompanying Mr Kim during a flight drill inspection.
He appears to be the fourth chief of staff since Mr Kim took over in 2011, as opposed to three during his father Kim Jong-il’s 17 years in power.
The reports of Gen Ri’s execution came days after the North launched a long-range rocket, which critics say is a test of banned missile technology. In January the North carried out its fourth nuclear test.
Some observers say the regime’s recent behaviour may be linked to Mr Kim wanting to shore up his position ahead of a rare congress of the Workers’ Party due in May. In May 2015 South Korea’s spy agency told parliament that the North’s defence minister Hyon Yong-chol had been executed for showing disloyalty.