The Japanese games firm will part company with incumbent The Red Consultancy. The agency has declined to repitch for the brief - thought to be worth £250,000 - after working for the Japanese company for the past three years.
The console manufacturer has announced its first drop in annual profits for six years, which have fallen to £1.62bn compared with the £2bn achieved the previous year.
Investors have blamed this on faltering sales of its Wii and DS devices. It is hoping to fight the dip by unveiling a hand-held 3D device, which the new agency will launch.
Nintendo head of communications Robert Saunders said his company was parting with Red 'on good terms'.
'There's nothing ominous in there, we're very grateful to the whole team for their three years' work. It's always useful to take a fresh look at what's out there,' he added.
However, insiders have suggested that the parting of ways was prompted by tough demands from senior bosses at Nintendo as it struggled for supremacy with Microsoft Xbox and Sony PlayStation.
Nintendo is using AAR to manage the pitch process and is expected to have an agency in place by mid-summer.
The brief up for grabs includes managing a 24-hour press office, campaign creation for new launches and supporting existing products.
Separately, Samsung has appointed Freud Communications for the launch of its new 3D TVs, despite Red being retained for ongoing consumer work.
Freud has been appointed by the South Korean technology company for a six-month campaign to launch the new 3D TV sets, which will go on sale in the UK soon.
Red won the UK Nintendo business from Cake in September 2007. Cake held the brief for ten years
Red also helped launch Nintendo's Wii Fit during its tenure. It promoted the brand's partnership with TV duo Ant and Dec
Fishburn Hedges is handling pan-European PR for Nintendo, having won the account in September 2008.