Wang, who attended the flag hoisting ceremony at Islamabad's Convention Centre, said China and Pakistan had stood by each other in difficult times and "this friendship will stand the test of time and grow with coming generations", Dawn reported.
The ceremony began with a 31-gun salute here, after a flag hoisting event by President Mamnoon Hussain.
Prime Minister Shahid Khaqan Abbasi and all three chiefs of the country's armed services were present on the occasion that marked the day when Pakistan and India got freedom from British colonial rule.
A 21-gun salute was observed in the provincial capitals and commemorative ceremonies were held in all major cities, the media reported.
Hussain said on the occasion: "Let us join hands for development and prosperity of the motherland by keeping aside our differences. Let us promote love and harmony by overcoming hatred and misgivings."
Army chief General Qamar Javed Bajwa on Sunday midnight hoisted the largest national flag in the history of Pakistan at the Pakistan-India border at Wagah. The 120x80 feet flag was hoisted on a 400-feet pole.
He said: "We will execute each and every terrorist in Pakistan."
And in an obvious reference to Afghanistan and India, he said he wanted "to tell our enemies, whether they are in the in east or west," that Pakistani soldiers would never bow to them.
Acknowledging Pakistan's "internal and external challenges", he added: "Any power that will aim to weaken Pakistan, the Pakistan Army and all other institutions will foil their attempts."