The 50-year-old man was held on suspicion of misconduct in a public office by officers from Operation Elveden.
Scotland Yard said a 43-year-old woman was also arrested at the address in north west London.
She was held on suspicion of aiding and abetting misconduct in a public office and money-laundering offences.
The pair were arrested at their home at 6am and are being questioned at a central London police station.
Police said the operation was sparked by information supplied by News Corporation's management standards committee (MSC), which was set up in the wake of the phone-hacking scandal that led to the closure of the News of the World last July.
Scotland Yard said in a statement:
"Today's arrests are the result of information provided to police by News Corporation's management standards committee.An HMRC spokesperson said:
They relate to suspected payments to a public official and are not about seeking journalists to reveal confidential sources in relation to information that has been obtained legitimately."
‘We can confirm a 50-year-old HMRC employee was arrested yesterday by Metropolitan Police Service officers in connection with Operation Elveden. For legal reasons we cannot comment further at this time.’
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