The couple seems to be back after a brief separation over Stewart's involvement with married director Rupert Sanders.
Pattinson and Stewart were seen hugging and kissing in a series of photographs, reported TMZ online.
In one photograph, Pattinson offered a drink to Stewart, who seemed to have just come out of a pool wearing a bikini.
In another shot, they were seen sharing a kiss, and one other picture showed them embracing each other.
Previously the 26-year-old actor was caught celebrating a friend's birthday with Stewart at Chateau Marmont in Hollywood.
According to a source, they whispered to each other intimately and even sneaked into a garden from a private side entrance.
The famous couple hasn't made an official public appearance together so far.
Stewart's new house is located near Pattinson's home.