If this forecast proves to be correct, it will mean a 19.7 per cent increase on the 305.8 million units shipped last year.
Similarly, the technology research company believes that all regional markets will return to growth over the next 12 months, with the sector remaining "robust" as demand for PCs continues.
George Shiffler, research director at Gartner, said: "The PC industry will be overwhelmingly driven by mobile PCs, thanks to strong home growth in both emerging and mature markets."
He added that mini-notebooks will also contribute to the growth of the sector, although they will face competition from ultra-low-voltage and next-generation tablets in the future.
Another market that Gartner expects to make positive gains in 2010 is identity and access management.
It is thought that revenue could reach $9.9 billion (£6.58 billion) this year, marking an eight per cent increase on 2009's figures.
