{{Infoboks krigsskip
| navn = ARA «Veinticinco de Mayo»
| bilde = 25 de Mayo.jpg
| bildetekst = 
| flagg = Naval Jack of Argentina.svg
| land = Argentina
| klasse = «Veinticinco de Mayo»-klassen
| type = Krysser
| pennantnr = C2
| verft = OTO, Livorno
| bestilt = 
| kjølstrekking = 29. november 1927
| sjøsatt = 11. august 1929
| overtatt = 
| operativ = 11. juli 1931
| utavtjeneste = 24. mars 1960
| skjebne = Solgt til opphugging 1962
| søsterskip = ARA «Almirante Brown»
| hjemmehavn = 
| karrierenote = 
| deplasement = 6&nbsp;800 tonn
| lengde = 170,80 m
| bredde = 17,82 m
| dybde = 4,66 m
| framdrift = Dampturbiner, 85&nbsp;000 hk
| hastighet = 32 knop
| rekkevidde = 8&nbsp;030 nautiske mil ved 14 knop
| pansring = 
| bestykning = 6 &times; 7,5" kanoner (3&times;2) <br />12 &times; 4" kanoner (6&times;2) <br />6 &times; 40 mm kanoner
| sensorer = 
| våpenkontroll = 
| kontroll = 
| kommandokontroll = 
| mottiltak = 
| mannskap = 780
| fly = 2
| note = 
}}

* ''For hangarskipet med samme navn se '''ARA «Veinticinco de Mayo» (1968)'''''

'''ARA «Veinticinco de Mayo»''' var en argentinsk krysser. Navnet, «25. mai», fikk hun etter den argentinske nasjonaldagen, datoen argentinerne begynte opprøret mot den spanske kronen, og navnet er brukt på flere skip i den argentinske marinen gjennom årene.

== Beskrivelse == 

ARA «Veinticinco de Mayo» var av klassen med samme navn som ved siden av ARA «Veinticinco de Mayo» bestod av søsterskipet ARA «Almirante Brown». Begge skipene ble bygget i Italia, noe de bar preg av til tross for store forskjeller fra samtidige italienske kryssere.

Hovedbestykningen bestod av seks 7,5" kanoner plassert parvis i tre tårn, to foran og et på akterdekket. Disse kanonene hadde en rekkevidde på opptil 27&nbsp;300 m. Sekundærbestykningen var seks 2&times;4" kanoner som også kunne brukes for luftvern. I tillegg førte hun to triple torpedorør og tolv 21" torpedoer.

{|
{{Infobox Ship Image
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|Ship caption=
}}
{{Infobox Ship Career
|Hide header=
|Ship country=Argentina
|Ship flag=30px|Argentine Naval Ensign
|Ship name=
|Ship namesake=
|Ship owner=
|Ship operator=
|Ship registry=
|Ship route=
|Ship ordered=
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|Ship builder=Odero Terni Orlando (Oto Melara)
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|Ship launched=
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|Ship captured=
|Ship fate=Scrapped 1960
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}}
{{Infobox Ship Characteristics
|Hide header=
|Header caption=
|Ship class=
|Ship type=
|Ship tonnage=
|Ship displacement=6,800t normal; 9,000t full load
|Ship tons burthen=
|Ship length=<span style="white-space:nowrap">560.3&nbsp;ft&nbsp;(170.8&nbsp;m)</span>
|Ship beam=<span style="white-space:nowrap">58.5&nbsp;ft&nbsp;(17.8&nbsp;m)</span>
|Ship height=
|Ship draught=<span style="white-space:nowrap">15.3&nbsp;ft&nbsp;(4.7&nbsp;m)</span>
|Ship draft=
|Ship depth=
|Ship hold depth=
|Ship decks=
|Ship deck clearance=
|Ship ramps=
|Ship ice class=
|Ship power=
|Ship propulsion=Parsons turbine, 2 screws
|Ship sail plan=
|Ship speed=32&nbsp;kt @ 85,000&nbsp;hp
|Ship range=8,000&nbsp;miles @ 14&nbsp;knots
|Ship endurance=
|Ship test depth=
|Ship boats=
|Ship capacity=
|Ship troops=
|Ship complement=600
|Ship crew=
|Ship time to activate=
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|Ship EW=
|Ship armament=Six 7.5&nbsp;inch <br>Twelve 4&nbsp;inch DP <br>Six 40&nbsp;mm AA guns <br>Six 21&nbsp;inch torpedo tubes
|Ship armour=Deck: 1 inch <br>Sides: 2.8 inch <br>Conning tower: 2.3 inch <br>Turrets: 2 inch
|Ship armor=
|Ship aircraft=Two, one catapult
|Ship aircraft facilities=
|Ship notes=
}}
|}

The '''ARA ''Veinticinco de Mayo''''' was a cruiser which served in the Argentine Navy through World War II. The English translation of the name is the Twenty-fifth of May, which is the date of Argentina's May Revolution in 1810.

The ''Veinticinco de Mayo'' was built in ''Veinticinco de Mayo'' class of cruisers.  Three vessels were to be produced, but in the end, only ''Mayo'' and her sister ship ''Almirante Brown'' were acquired, both in 1931.

These ships were unusual in several ways. First, they carried 7.5 inch guns, only the third class of warship to do so. Also, like the Italian ''Zara'' class and other Italian-built warships of the era they carried their floatplanes under the foredeck and launched them from a fixed catapult over the bows.