The 9,000-square-metre park (about 2.2 acres) lies in the southwestern Damascus district of Kafr Sousa, atop the ruins of recently bulldozed homes.
The opening ceremony, which came as Islamic State group militants battled rebels in a district in southern Damascus, was attended by deputy Foreign Minister Faisal Moqdad.
He called Kim, described by rights organisations as a brutal dictator, "a historic ruler and leader, famous for his struggle to liberate and build his country" .
"For this reason, he deserves to be honoured in Syria," Moqdad said.
In response to a question about the international community's criticism of the North Korean founder, Moqdad told AFP that "whoever criticises (Kim) is absurd and stupid."
Moqdad also praised North Korea for "standing with Syria against terrorism".
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The Syrian regime uses the term "terrorist" to describe all of its opponents -- from non-violent activists to jihadist fighters.
The street adjacent to the park is also named for Kim and stretches for one kilometre (less than a mile).
North Korea's ambassador to Syria Jang Myong said the park was "an expression of the respect and love that Syria, as a party, a government, and a people have for the great leader Kim Il-Sung."
Syria's conflict is "the result of the conspiracies and plans of the United States... to bring down the legitimate and independent regime, and to exert a monopoly over the Middle East," he said.
Syria's war began with peaceful anti-government demonstrations but has spiralled into a brutal civil war, leaving more than 240,000 people dead.
Kim Il-Sung led North Korea from its establishment in 1948 until his death on July 8, 1994.
North Korea, which has pushed ahead with its nuclear and missile programmes, is under multi-layered UN sanctions and diplomatic isolation.
It has maintained military ties with Syria's autocratic regime for several years, helping it build a nuclear facility that was destroyed by an Israeli raid in 2007.