Police say 33-year-old Cheryl Stone of Clinton, and 22-year-old Sara Pontbriand of Waterville robbed the coffee shop.
An employee at the Kennedy memorial Drive location called 911 just before midnight on Saturday, saying someone was at the drive-through window trying to steal some cash.
An officer arrived on scene seconds later and arrested Stone.
Police say she had $1,700 in cash, that had just been stolen.
Stone was recently fired from the Dunkin Donuts. The other woman, Pontbriand, was working at the time of the robbery.
She was arrested Sunday.
Both remain at the Kennebec County jail on $5,000 bail.