Subtly showing off her toned shoulders and strong arms, the 45-year-old styled an asymmetrical style dress with a block black and white pattern.
The floor-length number was a similar silhouette to the silk number she had worn earlier in the day for the Grand Prix, though this outfit appeared to be far more glamorous.
Princess Charlene stayed true to her style with the Valentino gown, sporting the popular one-shoulder design that is her go-to for public engagements.
She accessorised the two-toned maxi dress with designer black heels, a clutch bag and statement silver jewellery.
Opting for more dramatic makeup than her daytime look, the Monaco royal looked sunkissed with a lightly bronzed complexion.
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While Charlene often re-wears accessories and footwear, she debuted the monochrome dress for the special occasion.
The royal was wearing the Valentino one-sleeve, two-tone silk-cady gown, which retails for $11,000 (£8,910).
Despite opting for a second new dress on the day of the Monaco Grand Prix, Charlene did re-style her designer sandals.
Peeking out from underneath the long dress, the mother-of-two donned a classic black strappy heel.
The exact style is the “initiale ankle strap black suede sandals” by Hermes. Valued at around £372, the luxury high-heeled shoes are made of suede goatskin with gold-plated buckles.
To finish the effortless outfit, the chic royal was adorned in ornate jewellery, including diamond earrings and an opulent bangle.
The former Olympic swimmer’s earrings appear to be an old favourite – the Panthère de Cartier earrings with diamonds, sapphires, and onyx.
As expected for the stylish royal, the expensive jewels are valued at $192,000 (US), which is equal to £155,564.
In a bold move away from her trademark platinum locks, Charlene debuted a richer, dark auburn hairstyle in her trademark pixie cut.
The royal showed off her new look while stepping out for the Grand Prix alongside other members of the Monaco Royal Family yesterday afternoon.
While the Princess opted for a more sleek look earlier in the day, her short hair was more textured for the evening occasion, though still in a neat side parting.
To complete the glamorous ensemble, Charlene’s elegant makeup look comprised of dewy skin, light brown smokey eyes, a black winged liner, and glossy nude lips.