Food and medical supplies have arrived in the town of Douma, the International Committee for the Red Cross said.
It follows a pause in Syrian government air strikes overnight, with the situation in the besieged enclave on Friday described as "calm".
A previous delivery of aid to the region was cut short amid shelling.
"Today, they will deliver the remaining aid that wasn't delivered during the previous convoy of 5 March," a spokeswoman for the International Committee for the Red Cross (ICRC), Ingy Sedky, said.
"We also have some positive indications that a bigger convoy with additional supplies including medical items might happen next week," Ms Sedky added.
Friday's delivery is the third attempt this week to get humanitarian aid to civilians trapped by the fighting in the region on the edge of the Syrian capital, Damascus.
On Monday, a convoy of 46 trucks delivered some provisions to Douma but was forced to turn back.
A second attempt was later made to deliver the aid that agencies had failed to offload, but this was cancelled at the last minute due to security concerns.
While ICRC officials expect this latest convoy to successfully deliver its cargo, humanitarian organisations say it is not nearly enough aid for the estimated 400,000 people trapped in the area.
More than 900 civilians have been killed in the Eastern Ghouta region since the Russian-backed government assault was launched on 18 February, according to the UK-based Syrian Observatory for Human Rights (SOHR), which has a network of sources on the ground.
On Friday, the air strikes reportedly ceased briefly, with the enclave seeing its calmest night in more than a week, the SOHR said.
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