ComScore figures show Google way ahead of its two search rivals with 61.8 percent of the market, racking up a 0.2 percentage point increase on April.
While the once mighty Yahoo could only muster 20.6 percent of search market, the firm at least managed to achieve a 0.2 percent improvement when compared to April.
Microsoft remains in third place accounting for just 8.5 percent of May's search activity, dropping 0.6 percentage points from the 9.1 percent in April.
Year-on-year comScore figures show Google's overall market share increasing by 28.4 percent, compared to a two per cent decline for Yahoo and a 2.8 percent rise for Microsoft.