The Freedom House think tank has downgraded Hungary to only “partly free” because of “sustained attacks on the country’s democratic institutions”.
He has also described migrants as “Muslim invaders” and “poison”, shut down a critical radio station and been accused of using antisemitic tropes.
After the meeting, a Downing Street spokeswoman said: “The leaders discussed the importance of the UK and Hungary working together bilaterally to increase security and prosperity in our countries, and to address global challenges such as climate change.
“The prime minister raised his significant concerns about human rights in Hungary, including gender equality, LGBT rights and media freedom.
“The leaders also discussed a number of foreign policy issues including Russia, Belarus and China. The prime minister encouraged Hungary to use their influence to promote democracy and stability.”
Mr Orban told reporters that the pair also talked about finding “a way to cooperate in a post-Brexit period”.
He became only the second EU leader to travel to the UK since Brexit, in what was widely seen as Mr Johnson’s attempt to find new allies as well as send a signal to his core supporters.
Before the meeting, business secretary Kwasi Kwarteng claimed it would be “irresponsible” not to “build bilateral relations” with Mr Orban after Brexit.
But, in a letter to Mr Johnson, the Liberal Democrat leader Ed Davey wrote: “When you decide to invite leaders of other countries to Downing Street, your choice matters.
“It sends a signal to our allies, to our partners, to people in Britain and around the world, of the UK's values and commitments.”
The Hungarian leader has twice blocked the EU from issuing statements condemning China for actions in Hong Kong.
And, last year, he pushed Brussels to lift sanctions on Belarus, before a Ryanair flight was diverted last week so authorities could arrest a prominent journalist who has been critical of the regime.
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