Andrea and Tatiana, whose romantic royal wedding took place in August, were spotted in Paris as they attended the opening of luxury brand Moncler's new flagship store along with Olivia Palermo and model boyfriend Johannes Huebl.
The new husband and wife, who became parents to baby Sacha on 22 March, smiled as they left the fashion house's party with a group of friends.
A regular at Paris Fashion Week Tatiana, who co-runs the ethical fashion company Muzungu Sisters, sported a beaded red bolero jacket, a black shirt and leather trousers.
The fashionista accessorised her outfit with black loafers and a clutch bag while her husband Andrea sported jeans, a white shirt and a leather jacket.
Andrea and Tatiana said 'I do' in the grounds of the Prince's Palace on 31 August.
The bride kept true to her boho style and wore a chic bridal gown by Missoni, silver flat sandals and let her glossy brunette locks loose which she adorned with a simple floral headpiece.
Following the ceremony it was time to celebrate in style and Andrea and Tatiana were joined by their 400 guests for an el fresco lunch next to the Palace's pool.
Among the elite guest list were the likes of Greek shipping heiress Eugenie Niarchos, the Missioni fashion family and Tatiana's influential New York-based siblings.
Andrea's royal family, including Prince Albert II of Monaco, Princess Charlene, Princess Caroline and Charlotte Casiraghi also witnessed the couple's nuptials.