The action of 15 June 1780 was a minor naval engagement took place during the American War of Independence between a French privateer frigate and a Royal Navy 32-gun fifth-rate HMS Apollo off the coast near Ostend.

Apollo's opponent was the 26-gun French privateer Stanislaus, and after a period of tacking, the two engaged in broadsides while running for Ostend.

Lieutenant Edward Pellew who succeeded to the command continued the battle eventually driving the Stanislaus on shore not far from Ostend.

[2] A Royal Marine detachment sent ashore later captured the Stanislaus and was brought into the navy as HMS Proselyte.

[2] On the 18th, Lord Sandwich wrote to Pellew: "I will not delay informing you that I mean to give you immediate promotion as a reward for your gallant and officer-like conduct.