The announcement follows the news last month that Royal Caribbean strategic account manager Vicky Billing would join Hays as head of cruise.
Mould, who has worked in travel for 25 years, including as a regional sales manager for Princess Cruises, will take up her post on March 6.
She said: “I am very excited to be joining John, Vicky and the Hays Cruise team.
“The opportunity within the cruise sector is constantly growing and I look forward to taking Hays from strength to strength.”
Billing, who Rachel will report in to, said: “I am delighted for Rachel to be joining the team as my assistant head of cruise.
“Her passion, dedication and knowledge will be crucial in delivering the Hays cruise agenda.”
TTG reported in November that Hays Travel was considering acquisitions in the cruise space.
The firm’s managing director, John Hays, said: “This appointment adds to the strength of our cruise team.
“Rachel brings with her a wealth of experience in the cruise market, and will be working alongside Vicky to increase our overall cruise sales and develop our own Hays Cruise product."