The pair, who married in a surprise secret New York ceremony last month, stunned onlookers at the Manhattan after-party for the Cinema Society & Dior Beauty screening of her new film 'The Whistleblower' with their affection and disregard for onlookers.
A source told People: "When Daniel arrived on the roof deck, he embraced Rachel and gave her a long tender kiss on the lips - it was very romantic. I wanted to be part of that kiss."
Another onlooker added: "It was very hot."
Rachel, 41, arrived first to the event and was visibly delighted when her spouse arrived, dressed in a casual T-shirt and baseball cap.
One insider told Us Weekly magazine: "Rachel's eyes lit up when she saw Daniel. They were all over each other when they were together. He put his arms around her and they definitely exude being in love."
While the pair were comfortable showing their affection for one another, Daniel recently insisted he will never speak about his wedding or relationship with Rachel.
Rachel and Daniel, who star in horror movie 'Dream House' together, which was filmed throughout 2010 and is due to be released in September, began dating in December and tied the knot in front of just four people.
The actress split from director Darren Aronofsky last year. They have a five-year-old son Henry together.