The court Friday refused to annul the results of the voting, which opposition parties and international observers had said was marred by irregularities.
"None of the complaints were supported with the necessary proof," said Supreme Court President Mamadou Sylla.
The ruling gives President Alpha Conde's ruling RPG party the majority of seats in Guinea's Parliament; however not an absolute majority in the 114-sear legislature, the BBC said.
The RPG holds 53 seats. The main opposition UFDG party holds 37 seats and former Prime Minister Sidya Toure's UFR party has 10.
The election was held to replace the transitional government that was in place since military rule in Guinea ended in 2010. The run-up to the voting featured incidents of ethnic and religious tensions.