The junior army officers and soldiers have been arrested in the capital, Conakry, in a series of swoops on army barracks and private homes, the International Regional Information Network report said.
The government has not given any reason for the wave of arrests, which were described by military sources as routine checks.
The security sweep began during the run-up to presidential elections scheduled for Dec. 21. All of Guinea's main opposition parties have boycotted the vote, which is virtually guaranteed to see President Lansana Conte returned to power for a further seven years.
Conte, who has ruled the poor West African country with an iron hand since coming to power in a 1984 coup, will be opposed by only one minor challenger.
On Nov. 1,in a speech at Camp Samory, the main military barracks in Conakry, Conte warned the army not to try and pull a coup.