After a boiler cleaning from 7–15 May, "Ivanhoe", , and , laid 164 mines off the Hook of Holland on the night of 15/16 May. Three German minesweepers were later sunk by this minefield on 26 July. Three nights later, the same three ships, reinforced by "Intrepid", "Impulsive", and the auxiliary minelayer laid a minefield off the Dutch coast. "Princess Victoria" struck a German mine on the voyage home and was sunk; the destroyers rescued the ship's survivors. They laid five more minefields off the Dutch coast before the end of the month. On 29 May, the ship was transferred to the Dunkirk evacuation effort and ferried 930 troops to Dover that day. She also took aboard the crew of the badly damaged destroyer and then scuttled "Grafton". She was withdrawn from the evacuation on 30 May as too valuable to risk, but this decision was reversed the following day and "Ivanhoe" evacuated 1,290 men to Dover. On the morning of 1 June, already having loaded troops, the ship was attacked off Dunkirk harbour by German aircraft. Two bombs missed to port and starboard, but the third detonated above the upper deck and flooded the two forward boiler rooms. The bomb killed 26, including five soldiers, and wounded many others. Most of the troops and wounded were taken off by the minesweeper and the destroyer . No. 3 boiler room was still operable and the ship reached Dover under her own power.