The decision "was unanimous" to grant the award "with extraordinary mention to the comandante president Hugo Chavez," said the head of the awards jury, Milagros Perez.
"The history and practice of journalism can only be divided in two moments -- before and after comandante Chavez," Perez said.
A journalists' association cried foul, saying Chavez had made a habit of closing down media outlets.
President Nicolas Maduro, who succeeded Chavez, gave the award to Maria Gabriela Chavez, one of the late president's daughters, who cried when shown a video montage of her father.
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Chavez's was constantly on TV, either talking to supporters or giving speeches, and he hosted a live radio call-in show, called "Alo Presidente."
Chavez also embraced Twitter with a passion, and had more followers than any other Latin American president.
The award was delivered "with the conviction that the commander deserves this prize, and ... That the Venezuelan people, I'm certain, absolutely support this acknowledgement," said Maduro at the award ceremony.
According to the jury, Chavez's folksy, blunt style and his broadcast presentations "revolutionised" communications "not only in Venezuela, but at an international level."
Those reporters, represented by the National College of Journalists, blasted Chavez for being "responsible for the closure of innumerable news media outlets during his time in government, leaving scores of colleagues out of work."
More than once Chavez "publicly ridiculed" reporters when they asked him "uncomfortable questions," the statement read.
The posthumous award follows the sale in May of the Globovision TV network, which for years opposed the Chavez regime. Many staff members quit after the network adopted a more "centrist" political viewpoint.