David Lammy is being investigated over allegedly failing to declare £27,000 of financial interests.
The Parliament’s Standards Commissioner has launched the probe into the Tottenham MP over the late declarations of earnings and hospitality.
The shadow Foreign Secretary is being investigated for alleged breaches of the MPs Code of Conduct relating to four different categories.
It is believed to relate to Mr Lammy’s payments for speeches during Black History Month last year, which were not declared until May this year.
Mr Lammy’s invites to Tottenham Hotspur football club are also thought to be under scrutiny.
A spokesperson for Mr Lammy said: “David Lammy takes his declaration responsibilities seriously. As soon as it was brought to his attention he wrote to Registrar of Members’ Financial Interests to apologise for the administrative errors in his office which led to late declarations in December last year.
“He has assured the registrar that he has put revised systems in place so that declarations are made in a timely manner. We are happy to provide the Parliamentary Standards Commissioner with any further information.”
It is understood Mr Lammy has already written to the Registrar of Members’ Financial Interests apologising for the oversight and errors that led to a number of late declarations for payments received for speaking engagements last year.
The Commissioner Kathryn Stone last week also launched an investigation into Labour leader Sir Keir Starmer, who is alleged to have broken the rules by declaring gifted football tickets and book royalties worth more than £18,000 too late.
Ms Stone is currently investigating four MP, three of which represent London constituencies.
Home Office minister and Croydon South MP Chris Philp and Conservative backbencher, Andrew Bridgen are also subject to inquiries.