She took gold for Scotland in the women's under-48kgs final with victory over India's Sushila Likmabam in the event at the SECC.
Les than half an hour later her sister Louise won gold in judo's -52kg class.
Kimberley Renicks said: "It is absolutely brilliant. It is what I had been hoping for and what I have wanted for the last two years.
"The crowd have been behind all of us and it has been a great start to the Commonwealth Games.
"I could not have done it without Team Scotland and Judo Scotland, all of the fans, the family who have supported me all the way.
"If they had not put the effort in to get me to all of these places, I would not have been here today."
She added: "It has been really tough, because I was against girls I had never fought before, so you don't know how they are going to be.
"In judo you can win in the first 10 seconds or last four minutes, and I happened to win my fights pretty fast, which was good."
Louise Renicks said of her victory: "I have always believed I could get this medal, now I have got it, my job is done, and I am feeling brilliant, really proud of myself.
"I watched a bit of my sister's fight, where she won and then got her medal, but I had to keep myself focused.
"My mum and dad are here, and it is a really emotional moment, I was a bit upset when I came off the mat.
"I heard the Brownlee brothers won for England tonight, so now it is two families who can celebrate.
"I feel really proud with us getting the first gold medals for Scotland and there is much more to come."
In the pool Scotland's Hannah Miley won the gold medal ahead of England's Aimee Willmott in the women's 400m individual medley at Glasgow 2014.
It meant the 24-year-old Scot successfully retained the title she won in Delhi in 2010, while for Middlesbrough's Willmott a silver medal represents a best career return.
Glasgow's Michael Jamieson lost out to Ross Murdoch from Alexandria in the 200m breaststroke. Murdoch came first and Jamieson second in a one-two for the home nation.
Her win came soon after Scotland celebrated its first medal when Aileen McGlynn and Louise Haston won silver in para-cycling.