Although Lam had an opened frame in the eighth, the gap was simply to wide for Chan to mount any sort of comeback eventually going down to the champion, 171-212. The victory for Lam gave Macau their second straight win in the women's division.
Patricia Hui Tong had first won the women's crown for Macau last year after she beat Hong Kong's Vanessa Fung.
"My initial aim was not to be knocked out in the first round and therafter, I was focusing on trying to take one game at a time," said the delighted 35-year-old teacher, who turned from spinning to hook style last year.
"Reaching the finals was already a great achievement for me and to win is a bonus. I've to thank my coach, Daniel Yiu for so much guidance given to me during my transition from spinnng to hook."
The champion reached the finals after she narrowly defeated Chan Shuk Han, 216-212 in the second semi-final. Chan advanced to the finals by beating another Macau team-mate, Filomena Choi, 200-187 in the first semi.
Top seed, Milki Ng of Hong Kong was ousted by Filomena, 165-184 in the second round while Lam edged Thailand's Siraya Chongvarin, 171-160 in her Round 2 match.