The attempt, by the country's National System of Youth and Children's Orchestras, known as "The System", would beat a Russian record set two years ago and will be judged by Guinness in the next 10 days.
"The System" counts some 350,000 children and youths among its rank, playing in a network of 180 orchestras.
Saturday's musicians, wearing white, played Piotr Ilich Tchaikovsky's Marche Slave for 10 minutes at Caracas' military academy.
"It is a pleasure to be at the official attempt via video," Guinness expert Susana Reyes said.
The current record was set in Saint Petersburg, when 8,097 musicians played together.