Vice president Emili Rousaud revealed earlier in the week that he had been asked to stand down as Bartomeu sought to dispense with four members of the board.
Rousand and fellow VP Enrique Tombas sent a letter on Thursday together with four other directors, Silvio Elias, Maria Teixidor, Josep Pont and Jordi Calsamiglia, announcing they had handed in their notice.
In it, they outlined the reasons for resigning, which include Barca’s management of the social media scandal earlier this year, how the club is reacting to the current crisis caused by coronavirus and further discrepancies with the president.
"We hereby want to communicate that the directors below signatories have transferred to President Bartomeu our decision to irrevocably resign from our status as FC Barcelona executives," the letter said.
"We have reached this point by not being able to reverse the criteria and forms of management of the club in the face of the important challenges of the future and, in particular, from the new post-pandemic scenario.
"We must also highlight our disillusion over the unfortunate social media episode, known as 'Barcagate', of which we found out through the press."
The directors went on to call for compensation to be provided and claimed it had been an honour to serve their 'beloved Barca'.
Earlier this week, Rousand claimed that Bartomeu had agreed to follow the majority vote on bringing forward presidential elections, only to go back on his word after it was established most were in favour of a vote this summer instead of next year.