Andrew Marcus, who was an account manager at the agency, starts this week, reporting to the museum's head of comms Antony Robbins.
Marcus said: 'My priorities will be to deliver a first-class service to the media, build the brand, and make the Museum of London a must-see destination for every visitor to the city during the Olympic year.'
His responsibilities include day-to-day management of the press office, brand development and partnerships.
One of the first events Marcus will work on is the Dickens and London exhibition, which starts on 9 December. The museum is also launching an iPhone and iPad app to allow users to follow in Dickens' footsteps through the capital.
