Malcolm III (Scottish Gaelic: Máel Coluim mac Donnchada), (1031 – November 13, 1093), also known as Cenn Mór (anglicised as Canmore, hence Malcolm Canmore) meaning Big Head in the Gaelic language, was King of Scots. Malcolm is an anglicisation derived from a Latin form, Malcolmus. The name Máel Coluim means Servant of Columba, after the devotional pattern of many medieval Scottish names (c/f Máel Ísu' (Malise), servant of Jesus or Gilla Coluim, also servant of Columba). He was the eldest son of King Duncan I and first king of the House of Dunkeld.

In 1040 his father was killed in battle by his cousin Macbeth who became the new king. Malcolm found refuge in the Kingdom of England under the protection of King Harthacanute of Denmark and England. In 1042 Harthacanute died and was succeeded to the throne of England by his half-brother King Edward the Confessor. In 1053 Edward finally agreed to help Malcolm gain the throne of Scotland by offering him an army. Malcolm's invasion of Scotland started in the same year.
Malcolm found support from the nobles of southern Scotland. He managed to kill first Macbeth in 1057 and then his successor King Lulach I of Scotland in 1058. He then succeeded Lulach as king. He was crowned at Scone Abbey, Perth and Kinross, on April 25, 1058. He married Ingibjorg, widow of the Earl of Orkney, in about 1065 and they had three sons, who were:
1. King Duncan (Donnchad)
2. Donald (Domnall) (d.1085)
3. Malcolm (Máel Coluim) (d. after 1094).
Ingibjörg was dead by 1070, when he wed Margaret.

He agreed on an alliance with England, sealed by his (second) marriage to Saint Margaret, Edgar Ætheling's sister. Margaret herself promoted the Roman Catholic Church in Scotland throughout Malcolm's reign. At that time, Christianity did exist in Scotland in the form of the Celtic Church, but varied from Roman Catholic practice in some respects e.g. the dating of Easter and the shape of monks' tonsures. Malcolm had several sons by Margaret - these became known as the Margaretsons. Malcolm and Margaret's children were:
1. Prince Edward (Etbard) of Scotland, killed 1093.
2. Edmund I of Scotland (Etmond)
3. Ethelred of Scotland, abbot of Dunkeld.
4. King Edgar I of Scotland (Etgair)
5. King Alexander I of Scotland (Alaxandair)
6. King David I of Scotland (Dabíd)
7. Edith of Scotland, also called Matilda, married King Henry I of England
8. Mary of Scotland, married Eustace III of Boulogne

Malcolm unsuccessfully tried to stop this influence by waging wars against the Norman kings of England after 1066. In 1072 he was forced to give an oath of subservience to William I of England. It is notable that while his first wife Ingibjorg's sons all bore Gaelic names, half of Margaret's bore Anglo-Saxon/English names and the other half standard continental names. At the time this was noted with displeasure amongst many in the Scottish court and amongst the public.

His war against William II of England in 1093 only led to the loss of Scottish territory to England. Malcolm died on November of the same year in an ambush at Alnwick during a battle against William's army. His eldest son by Margaret, Edward, also died in that ambush. Malcolm was succeeded by his brother Donald.

Malcolm established the Dunkeld dynasty which ruled Scotland from 1058 until 1286. Four of his sons (Duncan II, Edgar, Alexander I, and David I) became kings of Scotland, whilst a fifth (Edmund) ruled as co-ruler of Scotland with his uncle Donald III.