The two sides drew 1-1 in the first leg of the tie with Walid El Karti netting an 94th minute equaliser after a 54th minute Lucas Ribeiro opener at Loftus Stadium.
Fiston Mayele opened the scoring in the second round tie and Ahmed Samy seemingly put the result out of reach for Downs, while Iqraam Rayners gave the Betway Premiership side a glimmer of hope with his goal after 75 minutes.
Sundowns have now been losing finalists twice, but for Pyramids this was their debut campaign in the CAF Champions League.
A delighted Jurcic said on IOL: "We achieved the accomplishment and were able to win the African Championship, and we deserved it.
"We truly deserved this title. This trophy is a gift from God for our efforts."
The Croatian coach added: "I want to thank the players for everything they have done. They truly deserve to be African champions.
"I thank the supporters for their presence and their unwavering support. They played a vital role in our victory.
"There were many fans who came behind the team. I asked the Egyptian fans to support us, and I thank them for coming and for giving us the energy that helped us win. We — supporters from different clubs — were all together."