All-time leading scorer Ronaldo left for Italian champions Juventus in the off-season and Madrid have struggled to fill the void following four consecutive matches without a goal.
Madrid have lost three of those games, including last week's shock 1-0 LaLiga defeat at Deportivo Alaves, increasing the pressure on under-fire head coach Lopetegui.
Emery, however, is confident Lopetegui – who replaced Zinedine Zidane at the start of the season – can get Madrid back on track.
"Real Madrid must find balance without him and they need time to adapt," former Sevilla boss Emery said. "However, I think Julen will find it."
Emery added: "We cannot answer for Julen, but when it happens to me, I try to be patient, but it is difficult to ask for patience in football. I'm sure the goals will come for Lopetegui."
Sergio Ramos came out in defense of his manager, saying it would be "crazy" for the club to sack him so soon into his tenure.