During the Boxer Rebellion in 1900, both ships contributed landing parties to participate in the Battles of the Taku Forts and of Tientsin.

Already made obsolete by the increasing speeds of the cruisers the ship was designed to defend against, she was placed in reserve in 1904, although Barfleur often participated in the annual fleet manoeuvres.

After being sold for scrap the following year, Barfleur got jammed underneath the piers of a swing bridge on her way to the scrapyard, forcing it to remain open and blocking traffic while she had to be freed.

The engines were designed to produce a total of 9,000 indicated horsepower (6,700 kW) which was intended to allow the ships to make a speed of 17 knots (31 km/h; 20 mph) using natural draught.

The engines proved to be slightly more powerful than anticipated and Barfleur reached 17.1 knots (31.7 km/h; 19.7 mph) from 99,934 ihp (74,521 kW) during her sea trials.

Using forced draught, she attained 18.54 knots (34.3 km/h; 21.3 mph) from 13,163 ihp (9,816 kW) although this often damaged the boilers and was officially discouraged.

[4] The four 32-calibre, breech-loading 10-inch Mk III guns of the main battery were mounted in two twin-gun, circular barbettes, one forward and one aft of the superstructure.

The armoured deck lay across the top of the waterline belt and consisted of 2 inches (51 mm) of mild steel.

The remaining three-pounders in the fighting tops were repositioned to the superstructure and the barbette hoods and the foremast was replaced by a signal mast.

[19] During the Boxer Rebellion, the ship put landing parties ashore which joined other forces in storming the Taku forts on 16–17 June 1900 and in relieving the foreign legations at Tientsin on 13–14 July 1900.

[16] Commander David Beatty (the future First Sea Lord) was serving aboard Barfleur when he was wounded at Tientsin during operations ashore.

[23] On 22 January 1902, she paid off at HM Dockyard, Devonport to begin a reconstruction at Portsmouth that included a partial rearmament that lasted until May 1904 when she was placed in reserve because she was already obsolete.

On 10 May, Barfleur recommissioned with a nucleus crew to serve as the flagship of the Rear Admiral, Portsmouth Division of the Reserve Fleet.

The battleship HMS Prince George relieved her on 4 March 1907 and Barfleur became the parent ship of special service vessels in the Portsmouth Division.

[24] She was sold on 12 July 1910 for £26,550 to C. Ewen, Glasgow and quickly resold to Bolckow, Vaughan & Co. for demolition at their works at Dunston-on-Tyne.