Odom celebrated at West Hollywood lounge Guys and Dolls with pals, including some of his L.A. Lakers teammates and, of course, Kardashian's little brother Robert, who stayed by the groom's side all night.
Across town, the bride-to-be chose to have an intimate soiree with mom Kris, sisters Kourtney and Kim, and a few close friends at Santa Monica's Viceroy hotel.
Among the guys who helped Odom toast away his bachelor days were Kourtney's boyfriend Scott Disick, Lakers player Ron Artest (who introduced the couple when Khloe hosted a welcome party for him a month ago), DJ Mbenga, Sasha Vujocic, R&B singer Pleasure P and producer/rapper Swizz Beatz, who hopped on the mic at the end of night to hype up the crowd for his friend who he said is "about to marry the love of his life."
Champagne ShowerOdom, who was dressed down in a white T-shirt and jeans, drank Armand De Brignac "Ace of Spades" champagne. At one point, Odom's pals started spraying champagne all over the groom. But during one quiet moment, Artest toasted his teammate, saying, "Big men get married in big ways, congrats my man!"
According to a guest, "The crowd went wild! Lamar walked around shaking hands with fans and well wishers, taking pictures and at one point dancing to Jay-Z and Rihanna's Run This Town.
At the end of the night, Odom personally thanked club owner Michael Sutton for "putting together a great night in such short notice," and the guys headed out just passed 1:30 a.m., according to the club's rep.
"We are thrilled that we could be part of Lamar's celebration," Guys and Dolls publicist Jaime Primak tells PEOPLE. "We couldn't be happier for he and Khloe and wish them all the best."
Ladies' NightMeanwhile at the Viceroy, Kardashian – wearing all black with a white wreath in her hair – hung out poolside with her family and friends, including Caroline D'Amore, who appeared on a recent episode of the bride's E! show Kourtney & Khloe Take Miami.
"Khloe and the girls enjoyed a night of great food, drinks and many laughs while celebrating poolside under the stars," says an eyewitness.
"She couldn't have looked better," adds the onlooker. "She seemed very excited about everyone showing up to celebrate her upcoming wedding."
Sharing Cute StoriesThe group of about 10 girls, who were being filmed for an upcoming episode of Keeping Up with the Kardashians, sat at a long table outside that was decorated with candles and pale flowers.
"They seemed to have a blast," said the onlooked. "There was a lot of cheering and toasting. Everyone was focused on Khloe."
The ladies dined on halibut, lobster bolognese, New York strip steak, butter lettuce salad and desserts with fresh berries. During the three-hour meal, the girls also sipped on wine and champagne cocktails while sharing cute stories about Khloe.
At 11 p.m., with the camera crew still in tow, the group headed upstairs to a hotel suite to continue the celebration in private.
With reporting by PERNILLA CEDENHEIM