The latest numbers from yesterday evening's show saw 1.3 million watching Love Island compared to 1.1 million for Big Brother.
It was a rise of 200,000 on Tuesday's show for Love Island, matching its launch night figure, while Big Brother slipped slightly on its Tuesday show.
Year-on-year its the same story with Love Island up on 2016 while Big Brother's slow decline continues.
Tonight will prove even tougher for Big Brother as it goes head to head with the start of the General Election results with its latest highlights show from 10PM on Channel 5.
Elsewhere last night, 2 million viewers watched the start of Channel 4's new school based drama Ackley Bridge at 8PM.
It was beaten by Tonight at the London Palladium on ITV which had 3.1 milion viewers for its latest episode, having taken a break last week for Britain's Got Talent.
As for the soaps, Emmerdale had 5.4 million viewers on ITV while Coronation Street continued with 6.5 million.
In the 9PM hour, The Met: Policing London continued with 3.4 million watching while Holiday Horrors: Caught on Camera had 2.2 million for ITV.
And finally, earlier in the day, in the battle of the tea time game shows The Chase continued with 2.4 milllion viewers to Pointless' 2.3 million.