Nearly 3,000 attempts were made to access pornographic websites from computers at Stormont in the last six months, it can be revealed.
Around 16 visits a day were recorded to pages with "adult content" via the internal system which is used by MLAs and their staff.
The Assembly said all the requests were blocked, and no inappropriate material was actually viewed.
While it is possible that some pages may have been accessed accidentally, it will raise questions about whether internet access is being misused by some people.
Ukip MLA David McNarry said he was disgusted and called for stricter rules on internet access.
"It is almost institutionalised porn-seeking – it is a very serious abuse of trust," he said.
"I would not like to think that anyone working for me and operating a computer is looking at pornographic material.
"A directive should go out to all MLAs and staff at the Assembly that this is unacceptable and must stop."
According to the Assembly, 2,970 attempts have been made to access websites with "adult content" since April.
The figures were disclosed following a Freedom of Information request by the Belfast Telegraph.
The response said: "In the last six months 2,970 requests were made to access websites classified as containing adult content.
"All 2,970 requests for this category of content were blocked by the Northern Ireland Assembly firewalls. During this period no websites classified as containing adult content were accessed by Assembly computers in Parliament Buildings."
The Assembly was asked if there were possible reasons for adult websites being accessed other than a deliberate attempt to view porn, but did not comment.
It was also unable to say how many people have access to Parliament Buildings' computer system.
Last month it emerged over 300,000 attempts were made to access pornographic websites at the Houses of Parliament in the past year.
Almost 850 attempts to click on adult websites were blocked at Westminster each day.
One particularly popular site was 'Out of Town Affairs', a dating site for those wanting to engage in extra-marital affairs, which garnered 52,000 hits in seven months.
The figure covered devices linked to the Parliamentary Network, including those used by MPs and peers, their staff and other employees.
Around 5,000 people currently work on the parliamentary estate.
It was uncomfortable reading for David Cameron, who has demanded that internet service providers do more to stop children viewing inappropriate content online.
The Prime Minister wants an "opt-in" system so customers have to ask service providers not to block adult content.
Online pornography was "corroding childhood" and "distorting" children's understanding of sex and relationships, he argued.