The Iranian has dominated the competition in recent years, triumphing in 2006 and 2010, and his second-round effort on Tuesday was enough to seal another title.
India's Vikas Shive Gowda was Hadadi's nearest challenger, while Ahmed Dheeb of Qatar threw a season's best 61.25m to take bronze.
China dominated the other athletics events in South Korea with gold medals in the women's pole vault, men's 110m hurdles and men's long jump.
And a further 10 golds were added to China's haul at the Games as they strengthened their grip on top spot in the medal table.
Wang Zhen and Shi Qinglan completed a clean sweep in the mountain bike cross country events, while there were also wins for Chinese pairings in the two diving finals.
Cao Yuan and Lin Yue took gold in the men's synchronised 3m springboard event with 460.86 points and Chen Ruolin and Liu Huixia were victorious in the women's synchronised 10 m platform.
The hosts dominated the bowling finals at the Anyang Hogye Gymnasium, gaining three of the four gold medals on offer, including Park Jong-woo claiming victory in the men's all events competition with 5047 points.
South Korea won four of the 13 sailing golds on offer, He Jee-min coming out on top in the men's laser and the pair of Kim Chang-ju and Kim Ji-hoon prospering in the 470 class.
Kim Hyong-jun took the men's singles title in the soft tennis as he beat Singapore's Edi Kusdaryanto 4-0, while Kim Bo-mi made it a South Korean double with a 4-1 win over Chen Hui in the women's competition.
China's Wang Qiang took the women's tennis final in straight sets against Luksika Kumkhum and Yoshihito Nishioka was a 6-2 6-2 winner over Lu Yen Hsun in the men's event.
Abdullah Sharbatli claimed Saudi Arabia's second gold of the Games as he won the jumping gold in the equestrian, the 32-year-old beating Japan's Satoshi Hirao and Taizo Sugitani to victory.
The taekwondo finals saw wins for Masoud Hajizavareh of Iran and Uzbekistan's Jasur Baykuziev in the men's disciplines, with Thailand's Chanatip Sonkham and Huang Yun Wen of Chinese Taipei securing glory in the women's under 49kilogram and under 53kg finals.
In the table tennis it was once again China who dominated proceedings.
Four years ago the team completed a clean sweep of all the medals in table tennis and they were again successful in the men's and women's team finals.
The men's Greco-Roman wrestling competitions came to a close in the Dowon Gymnasium with Iranians Habibollah Akhlaghi and Mahdi Aliyarifeizabadi claiming two of the four golds.
Park Ji-na will meet Yin Junhua in the women's lightweight boxing final after both secured semi-finals wins on Tuesday, while Luu Thi Duyen and Laishram Sevi had to settle for bronze after defeats.
In the women's middleweight final North Korea's Jang Un-hui will fight Li Qian.
China's final gold medals of the day came in the men's team skeet as the trio of Zhang Fan, Jin di and Xu Ying scored 366 points, beating Kuwait by 13 with Korea third a further two back.
In the individual event Kuwait claimed gold thanks to Abdullah Alrashidi's 16-12 win over Xu.
Hong Kong and Sri Lanka claimed cricket quarter-final wins, while Malaysia, India and Iran all secured wins in the Kabaddi.
The men's football and hockey finals will see heated rivalries reignite as South Korea play North Korea in the former, with India meeting Pakistan in the hockey.
Sepaktakraw's regu group matches saw wins for Thailand and Brunei, while the preliminary rounds of the softball and rugby got underway.
Elsewhere, the water polo and volleyball competitions reached the semi-final stage.