Philip Van Horne Lansdale (15 February 1858 – 1 April 1899) was an officer in the United States Navy.
Promoted to lieutenant 15 May 1893, he became executive officer of the protected cruiser USS Philadelphia upon her recommissioning at San Francisco 9 July 1898.
After visiting Honolulu for ceremonies which transferred the sovereignty of the Hawaiian Islands to the United States, Philadelphia, flagship of Rear Admiral Albert Kautz, Commander, Pacific Station, arrived Apia, Samoa, 6 March 1899.
An unstable political climate, created by rival Samoan factions and German presence, erupted into open hostility during the month.
With Lieutenant Lansdale in command, the landing party was ambushed and forced to retreat after a fierce fight near Vailele.