After 16 years in the UK, the brand is expected to open eight restaurants this year, adding to its 64 branches.
The account moves from Roche Communications, which has worked with the brand for around 12 years.
LightBrigade’s team will be lead by director Jo Marino, who will report to YO! Sushi head of marketing Graham Hawkey-Smith and senior marketing manager My Ly.
Hawkey-Smith said: ‘We were won over by the immediate chemistry with the LightBrigade team. The overall strategy they pitched was on a different level in terms of understanding how important social media is to a brand such as YO! Sushi.’
The agency will create a campaign for a product launch the brand has planned for June this year.
YO! Sushi is owned by private equity firm Quilvest and the company’s senior management team in the UK.