January 22 – Fall of the Ava Kingdom in Upper Burma.
February 2 – The Diet of Augsburg begins.
February 4 – John Rogers, burned at the stake in London, becomes the first Protestant martyr under Mary I of England.
February 8 – Laurence Saunders becomes the second Marian Protestant martyr in England, being led barefoot to his execution by burning at the stake.
February 9 – Rowland Taylor, Rector of Hadleigh, Suffolk, and John Hooper, deposed Bishop of Gloucester, are burned at the stake in England.
April 10 – Pope Marcellus II succeeds Julius III as the 222nd pope. He will reign for 22 days.
April 17 – After 18 months of siege, the Republic of Siena surrenders to the Florentine–Imperial army.
May 23 – Pope Paul IV succeeds Marcellus II as the 223rd pope.
June 1 – Treaty of Amasya between the Ottoman Empire and Safavid Persia concludes the Ottoman–Safavid War (1532–1555).
July 12 – Pope Paul IV creates the first Jewish ghetto in Rome.
September 25 – The Peace of Augsburg is signed between Charles V, Holy Roman Emperor, and the Lutheran Schmalkaldic League establishing the principle Cuius regio, eius religio, that is, rulers within the Empire can choose the religion of their realm.
October 16 – Two of the Oxford Martyrs, Hugh Latimer and Nicholas Ridley, are burned at the stake in England.
October 25 – Charles V abdicates as Holy Roman Emperor and is succeeded by his brother Ferdinand.
Russia breaks a 60-year-old truce with Sweden by attacking Finland.
Humayun resumes rule of the Mughal Empire.
Bairam Khan defeats Hindu forces at Panipat.
Collapse of the Adal Sultanate in the Horn of Africa.
The Muscovy Company is chartered in England to trade with Muscovy and Richard Chancellor negotiates with the Tsar.
English captain John Lok returns from Guinea with 5 Africans to train as interpreters for future trading voyages.
Richard Eden publishes The Decades of the Newe Worlde or West India, a translation into English of parts of Pietro Martire d'Anghiera's De orbe novo decades, Gonzalo Oviedo's Natural hystoria de las Indias and others including the first recorded use in English of the country name 'China'.
"Negro" – the Spanish term for "black person" – is coined.
Gresham's School is founded by Sir John Gresham at Holt, Norfolk in England.
William Annyas becomes the Mayor of Youghal in Ireland, the first Jew to hold such a position in Ireland.
John Dee is charged, but cleared, of treason in England.
Orlande de Lassus' first book of madrigals is published, in Antwerp.
Lorenzo de' Medici orders a violin from Andrea Amati of Cremona.
January 26 – Charles II, Lord of Monaco (d. 1589)
February 25 – Alonso Lobo, Spanish musician (d. 1617)
March 18 – François, Duke of Anjou, youngest son of Henry II of France and Catherine de' Medici (d. 1584)
March 21 – John Leveson, English politician (d. 1615)
March 31 – Elizabeth Stuart, Countess of Lennox, English countess (d. 1582)
April 21 – Ludovico Carracci, Italian painter (d. 1619)
April 25 – Naresuan, King of Ayutthaya (d. 1605)
April 28 – Karl Friedrich of Jülich-Cleves-Berg, Heir apparent of Jülich-Cleves-Berg (d. 1575)
May 5 – Queen Uiin, Korean royal consort (d. 1600)
May 9 – Jerónima de la Asunción, foundress of the first Catholic monastery in Manila, the Monastery of Santa Clara (d. 1630)
May 29 – George Carew, 1st Earl of Totnes, English Earl, general and administrator (d. 1629)
June 11 – Lodovico Zacconi, Italian composer and music theorist (d. 1627)
June 13 – Giovanni Antonio Magini, Italian mathematician, cartographer and astronomer (d. 1617)
June 16 – Duke Otto Henry of Brunswick-Harburg, Hereditary Prince of Brunswick-Lüneburg-Harburg (d. 1591)
July 6 – Louis II, Cardinal of Guise, Catholic cardinal (d. 1588)
July 17 – Richard Carew, English scholar (d. 1620)
August 1 – Edward Kelley, English spirit medium (d. 1597)
September 21 – John Thynne, English landowner and politician (d. 1604)
September 23 – Louise de Coligny, Fourth wife of William the Silent (d. 1620)
September 28 – Henri de La Tour d'Auvergne, vicomte de Turenne, duc de Bouillon, Marshal of France (d. 1623)
October 6 – Ferenc Nádasdy, Hungarian noble (d. 1604)
October 12 – Peregrine Bertie, 13th Baron Willoughby de Eresby, English Baron (d. 1601)
November 6 – Nyaungyan Min, King of Burma (d. 1605)
December 4 – Heinrich Meibom, German historian and poet (d. 1625)
December 27 – Johann Arndt, German Lutheran theologian (d. 1621)
Lancelot Andrewes, English clergyman and scholar (d. 1626)
Richard Carew, Cornish translator and antiquary (d. 1620)
Adam Sędziwój Czarnkowski, Polish nobleman (d. 1628)
Samuel Eidels, rabbi and Talmudist (d. 1631)
Joshua Falk, rabbi and commentator (d. 1614)
Henry Garnet, English Jesuit (d. 1606)
Elijah Loans, rabbi and kabbalist (d. 1636)
François de Malherbe, French poet (d. 1628)
Jan Zbigniew Ossoliński, Polish nobleman (d. 1628)
Okudaira Sadamasa, Japanese nobleman (d. 1615)
Konishi Yukinaga, Japanese Christian daimyo (d. 1600)
Moderata Fonte, Italian poet, writer and philosopher (d. 1592)
Maria van Schooten, Dutch war heroine (d. 1573)
January 14 – Jacques Dubois, French anatomist (b. 1478)
February 4 – John Rogers, English clergyman (burned at the stake) (b. c. 1500)
February 8 – Laurence Saunders, English clergyman (burned at the stake)
John Hooper, English churchman (burned at the stake) (b. c. 1497)
Rowland Taylor, English Protestant martyr (burned at the stake) (b. 1510)
March 14 – John Russell, 1st Earl of Bedford (b. 1485)
March 23 – Pope Julius III (b. 1487)
April 12 – Joanna of Castile, queen of Philip I of Castile (b. 1479)
April 18 – Polydore Vergil, English historian (b. 1470)
April 30 – Pope Marcellus II (b. 1501)
Gemma Frisius, Dutch mathematician and cartographer (b. 1508)
Henry II of Navarre (b. 1503)
August 25 – Thomas Howard, 3rd Duke of Norfolk (b. 1473)
September 8 – Saint Thomas of Villanueva, Spanish bishop (b. 1488)
October 5 – Edward Wotton, English zoologist (b. 1492)
October 9 – Justus Jonas, German Protestant reformer (b. 1493)
Hugh Latimer, English clergyman (burned at the stake) (b. c. 1487)
Nicholas Ridley, English clergyman (burned at the stake)
October 25 – Olympia Fulvia Morata, Italian classical scholar (b. 1526)
Stephen Gardiner, English bishop and Lord Chancellor (b. 1493)
Zhang Jing, Ming Chinese general (beheaded)
November 21 – Georg Agricola, German scientist (b. 1490)
December – Stanisław Kostka, Polish noble (b. 1487)
Year 1555 (MDLV) was a common year starting on Tuesday (link will display the full calendar) of the Julian calendar.