Members of the LGBT community enjoy comparatively more freedom in Lebanon than in most other Middle East countries but still have no rights and face constant harassment.
The first gay pride event in Beirut was held in 2017 but consisted mostly of conferences and workshops, whereas the opening of this year's edition was due to be a concert at on of the capital's best known venues.
"Religious institutions called for the cancellation of the concert, linking it to the promotion of same-sex marriage and associating it to debauchery and immorality," Beirut Pride said in a statement late on Wednesday.
Organisers said the entire schedule of events was suspended until further notice.
Beirut Pride said that the management of the theatre that had been due to host the opening party had received anonymous threats.
The former grand mufti of Lebanon, the country's top religious official, had issued a statement urging the authorities to stop the Beirut pride events.
Last year's edition was also suspended after one of the organisers was briefly arrested.
In July, a top Lebanese music festival cancelled a concert by Mashrou' Leila, which is arguably the country's best-known band and whose lead singer is openly gay.
Clerics had called for the cancellation of the concert in Byblos because some of the group's songs were deemed offensive to Christians.
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