The biggest property deal in the North's history was "seriously deficient", the Public Accounts Committee (PAC) said.
The cut-price sale of almost 1,000 properties by Nama, cost the Irish taxpayer €220m.
The PAC said the 2014 transaction was not well-designed and Nama's former adviser Frank Cushnahan should have been removed.
It also said key elements of the sale were influenced by one of the bidders, US firm Pimco, and the most active participants in the market for non-performing loans were not initially invited to compete.
The PAC report said: "The sales strategy pursued by Nama included restrictions of such significance that the strategy could be described as seriously deficient.
"Nama has been unable to demonstrate that by pursuing such a strategy that it got value for money for the Irish State in relation to the price achieved."
Nama was established in 2009 to take control of billions of euro of bad property loans at home and abroad which were undermining the finances of the Irish banks.
The entire Northern Ireland portfolio was sold to Cerberus, a US investment fund manager, for £1.1bn in a sale known as Project Eagle.
The report said Nama incurred losses on its Northern Ireland debts of €800m from 2010 to 2014 and the state ultimately recovered only 36% of the original value of the loans.
A Nama statement disputed the suggestion an extra £162m could have been raised through Project Eagle and said the overall losses would have arisen whether the portfolio was sold or retained in 2014.
A spokesman said: "It was the Board's commercial and considered judgment, in full knowledge of the financial implications, that the sale of the Project Eagle loan portfolio provided a better financial outcome than any alternative monetisation strategy.
"That was the Board's view in 2014 and it remains the Board's view today."
Businessman Mr Cushnahan was a member of the Northern Ireland Advisory Committee (NIAC) to Nama.
During 2011 and 2012 he admitted providing financial consultancy services, mainly on a non-fee basis, to six Nama Northern Ireland debtors.
PAC chairman Sean Fleming noted: "These debtors' connections accounted for approximately 50% by value of the Project Eagle loans.
"It is the opinion of the committee that Nama's failure to effect Mr Frank Cushnahan's removal from NIAC, following his disclosures in relation to consultancy services on behalf of a number of Nama's Northern Ireland debtors, was a failure of corporate governance by Nama."
Mr Cushnahan has consistently denied any wrongdoing.
According to the PAC chairman, when the Nama board was deciding to set its minimum price for the sale, it already had an indicative offer on the table from Pimco.
He said: "I believe that Nama was influenced by the Pimco offer when deciding on the minimum reserve price and key elements of the sales process."