More than 3,000 complaints were made to the TV watchdog following two interviews with Care Minister Helen Whately on Good Morning Britain earlier this month.
Another 600 viewers also complained about Piers’ interview with Health Secretary Matt Hancock on April 16.
In a statement, Ofcom said the GMB host is “well-known for his combative interviewing style” and viewers would expect him to challenge senior politicians.
An Ofcom spokesman said: “We assessed a number of complaints about Piers Morgan’s conduct while interviewing politicians about the UK’s response to the coronavirus public health crisis.
“Piers Morgan is well-known for his combative interviewing style and viewers would expect him to challenge senior politicians and hold them to account. His guests were given adequate opportunity to put their points across and counter the presenter’s criticisms.
“In Ofcom’s view, in line with freedom of expression, it is clearly in the public interest that broadcasters are able to hold those making political decisions to account, particularly during a major national crisis, such as the coronavirus pandemic.”
Responding to the news on Instagram, Piers said he’d been “emphatically cleared” and thanked his supporters.
“I’ve been emphatically cleared by OFCOM of treating Govt ministers ‘unfairly’ during this crisis,” he wrote.
“Verdict: ’Viewers would expect him to challenge senior politicians and hold them to account.
“Thank you to everyone that supported me.”
Ofcom said it received 1,981 complaints following Piers’ interview with Helen Whately on April 15.
A further 1,246 complaints were made following the minister’s Good Morning Britain appearance on April 22.
Piers defended the first interview, saying it was not as “uncomfortable” as the conditions for the carers on the front line of the coronavirus crisis.
During an animated interview, he asked Ms Whately for the number of health workers and care workers who had died from the illness.
She accused him of “shouting at me and not giving me a chance to answer your questions” and “attempting to score points”.
Some viewers accused Piers of “bullying” the politician while others praised him for “demanding answers”.
During Matt Hancock’s appearance on Good Morning Britain, the minister accused Piers of constantly interrupting him.
Ofcom said it received a further 266 complaints from seven of Piers’ political interviews during April.