After repairs at Truk, on 28 April "Okinoshima" was appointed flagship for Admiral Shima's Tulagi invasion force, which was part of "Operation Mo" (the invasion of Tulagi and Port Moresby in New Guinea). The Tulagi assault force began their landings on Tulagi on 3 May, with "Okinoshima" successfully landing troops of the Kure 3rd SNLF. However, the invasion force was attacked on 4 May by aircraft from the USS "Yorktown". Several transports and the destroyer , were sunk and "Okinoshima" suffered from a near miss, which resulted in her being towed to Rabaul for repairs.