Bhyan produced her best throw in her fourth attempt, 16.02m, winning the F32/51 event ahead of UAE's Alkaabi Thekra, who threw 15.75m.
The F32/51 class features athletes with significant impairment in hand function.
Bhyan had come into the competition on the back of a gold in the Indian Open Para Athletics Championship earlier this year.
India also secured three bronze medals on Tuesday courtesy Jayanti Behera, Anandan Gunasekaran and Monu Ghangas.
Ghangas finished third in the men's shot put F11, which covers vision impairment, and Gunasekaran in men's 200m T44/62/64 class, which deals with impairment in foot, ankle and/or lower leg but the athletes compete without prothesis.
Behera bagged the bronze in the women's 200m T45/46/47 event which is for athletes with limb impairment.
On Monday, javelin thrower Sandeep Chaudhary produced a stunning world record effort to win gold as India bagged 11 medals, including three gold, on a productive day.
IMAGE: Ekta Bhyan celebrates winning gold in the women's club throw event at the Asian Para Games.
Photograph: SAI Media/Twitter
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