Two MSF staff were among those wounded when the clinic in Taez, Yemen's third-largest city, was struck by coalition jets yesterday, it said.
The agency said it had repeatedly shared coordinates of the clinic with Riyadh in the days before the strike.
"There is no way that the Saudi-led coalition could have been unaware of the presence of MSF activities in this location," said Jerome Alin, MSF mission head in Yemen.
Battles have raged for weeks in and around Taez as loyalist forces clash with Iran-backed rebels for control of the strategically located city, which is seen as the gateway between south Yemen and the capital Sanaa.
A Saudi-led coalition has bombed rebel positions across Yemen since March.
The United Nations says more than 5,700 people have been killed in Yemen since then, nearly half of them civilians.
