The aid is urgently needed for hundreds wounded in fighting between pro-government forces and the Shiite Huthi rebels, who are allies of troops loyal to ex-president Ali Abdullah Saleh.
Coalition warplanes today launched raids in and around Sanaa, with at least 11 around Sanhan, Saleh's home town.
A raid on military targets in Amran province north of Sanaa killed eight rebels, medics said on the 18th day of the Saudi-led air campaign.
The International Committee of the Red Cross said its aircraft landed in Sanaa with medical equipment after weeks of intense fighting across the country.
"The new cargo is 35.6 tonnes, of which 32 tonnes is medical aid and the rest water purifying equipment, electric power generators and tents," ICRC spokeswoman Marie Claire Feghali said.
The Red Cross and the UN also sent planes to Sanaa yesterday, each carrying 16 tonnes of medicine and equipment, the first aid supplies to reach the capital since the air campaign began late last month.
More than two weeks of heavy bombardment against opponents of exiled President Abedrabbo Mansour Hadi and fighting between rival militias has prompted a UN call for a freeze in the violence.
UN humanitarian coordinator in Yemen, Johannes Van Der Klaauw, said an "immediate humanitarian pause in this conflict" was desperately needed to step up aid deliveries.
"The situation in Aden is extremely, extremely preoccupying if not catastrophic," he said, warning that the southern port city had fallen prey to "urban warfare" and "uncontrollable militias".
Yemen's second city Aden has seen some of the toughest fighting.
Today, pro-Hadi forces ambushed rebels aboard a 30-vehicle convoy which tried to enter a neighbourhood where oil refineries are located, Hadi loyalists said.
Thirteen rebels and four loyalist forces were killed, they added.
