The 20-year-old Argentinian on Monday moved to Rovers from Chelsea to start a temporary spell initially until January.
Di Santo has been brought in to bolster a forward line which has lost Roque Santa Cruz and Matt Derbyshire from last season, although he is likely to be joined by Hajduk Split striker Nikola Kalinic when the Croatia international receives a work permit allowing him to sign a £6million deal.
The 6ft 4in forward is keen to make an impression with Rovers having made just 16 non-scoring substitute appearances in 16 months for Chelsea.
New Stamford Bridge boss Carlo Ancelotti is keen for the youngster to gain vital experience and sees Ewood Park as the ideal place to do so.
"I am very happy to be here because I think Blackburn is a big team for me and I want to improve," Di Santo told Rovers Player.
"I want to do my best for Blackburn. For me it is important because I need to improve, score and be happy.
"I spoke with the manager (Sam Allardyce) and he convinced me to come here.
"I am very fast, I like to play with height and I will try to score every game if my friends cross to me."