The engagement party followed Gwyneth's beach-filled bachelorette bash in Mexico a couple days prior.
The Oscar victor and owner of life-style website Goop attended a lavish bash for 400 guests at the vintage Los Angeles Theatre on Saturday to celebrate her betrothal to TV producer Brad Falchuk, 47.
"Thank you #ryanmurphy for the most incredible evening to celebrate our (love)", she writes on Instagram alongside a picture from the party.
'There will never be adequate words to express our gratitude, ' said the GOOP founder.
But it wasn't the venue or Gwyneth's stunning dress that had everyone talking - it was an oxblood one-shoulder Giambattista Valli gown by the way - instead it was the star-studded guest list.
When the Oscar victor turned up at the bash in a maroon gown, it was reported the LA do was an engagement party. We feel like the luckiest people on the planet because we have all of you in our lives.
The traditional attire of the bride, in their opinion, brought mom Paltrow at the entrance to the theatre Blythe Danner was spotted with a garment bag, which bore the logo of a wedding designer Monique Lhuillier.
The Vogue cover girl was previously Wednesday to Coldplay singer Chris Martin, with whom she has two children - Apple and Moses.