Malaysian Indians or Indo-Malaysians are Malaysian citizens of Indian ancestry. Most are descendants of those who migrated from India to British Malaya from the mid-19th to the mid-20th centuries. Most Malaysian Indians are ethnic Tamils; smaller groups include the Malayalees, Telugus and Punjabis. Malaysian Indians form the fifth-largest community of Overseas Indians in the world. In Malaysia, they represent the third-largest group, constituting 7% of the Malaysian population, after the Bumiputera (combined grouping of ethnic Malays and other indigenous groups) and the Chinese. They are usually referred to simply as "Indians" in English, Orang India in Malay, and Yinduren in Chinese.

Malaysia's Indian population is notable for its class stratification, with a significant elite and a large low income group within its fold. Malaysian Indians large percentage of professionals per capita by constituting 15.5% of Malaysia's professionals in 1999 has been reduced with substantial population close to 40% is now considered the B40 category. In the 1984 census, up to 38% of the nation's medical professional workforce consisted of Malaysian Indians, but this has been since been reduced. In 1970, the per-capita income of Malaysian Indians was 76% higher than that of the Malay majority. Despite attempts by the Malaysian government to redistribute wealth since the 1970s through institutionalized racial policy, by 2005 Malaysian Indians still earned a 27% higher per capita income than that of the dominant Malay community.

Ancient India exerted a profound influence over Southeast Asia through trade, religious missions, wars and other forms of contact. Pre-colonial Malaysia was part of the Malay Kingdoms with Hindu-Buddhist influence such as Srivijaya, and the Majapahit, which formed part of a cultural region known as India. There is a possibility that the first wave of migration from India towards Southeast Asia happened during Asoka's invasion towards Kalinga and Samudragupta's expedition towards the South.

The Arab and Indian traders had travelled this region including the southern tip of South East Asia the peninsula with maritime trade, the Sailendra kings of Java were able to take control of the Peninsular and part of southern Siam. The kings welcomed Buddhist missionaries from India, accepting their teaching of the Mahayana sect, which spread through their territories. However, central and northeastern Thailand continued to adhere to the Hinayana teachings of the Theravada sect, which had been introduced by missionaries sent by the emperor Ashoka in the 3rd century BC. Another theory of the introduction of Buddhism after Indian arrived in the peninsula is that after Kalinga conquered lower Burma in the 8th century their influence gradually spread down the peninsula. The ancient Indian Kalinga was located in southeastern India occupying modern day Orissa and northern Andhra Pradesh. In the 7th century an Indonesian kingdom was named Kalingga after the aforementioned Kalinga in India. Chinese sources mention this kingdom (Holing) as a center for Buddhist scholars around 604 before it was overshadowed by the Sanjaya or Mataram kingdom. The most famous Kalingga ruler is Ratu Sima.

There is evidence of the existence of Indianised kingdoms such as Gangga Negara, Old Kedah, Srivijaya since approximately 1700 years ago. Early contact between the kingdoms of Tamilakkam and the Malay peninsula had been very close during the reigns of the Pallava dynasty (from the 4th to the 9th century CE) and Chola dynasty (from the 9th to the 13th century CE). The trade relations the Tamil merchants had with the ports of Malaya led to the emergence of Indianised kingdoms like Kadaram (Old Kedah) and Langkasugam. Furthermore, Chola king Rajendra Chola I sent an expedition to Kadaram (Srivijaya) during the 11th century conquering that country on behalf of one of its rulers who sought his protection and to have established him on the throne. The Cholas had a powerful merchant and naval fleet in the Indian Ocean and the Bay of Bengal. Three kinds of craft are distinguished by the author of the Periplus – light coasting boats for local traffic, larger vessels of a more complicated structure and greater carrying capacity, and lastly the big ocean-going vessels that made the voyages to Malaya, Sumatra, and the Ganges. In Malacca Sultanate, the Chitty people, played a huge role in Malacca's administration of the local ports such as Raja Mudaliar, Syahbandar (Chief of Port) of Malacca and Bendahara Tun Mutahir, a famous Bendahara of the Malaccan Sultanate.

Following the Portuguese colonisation of Malacca (Malaysia) in 1511, the Portuguese government encouraged their explorers to bring their married Indian women who were converted already to Roman Catholic Christianity, under a policy set by Afonso de Albuquerque, then Viceroy of India. These people were Goan Catholics (Konkani Catholics) and Bombay East Indians (Catholics of Marathi descent). Kuparis who were of mixed Samvedic Brahmin, Goan and Portuguese descent also arrived. Their children already intermarried with Malay population, losing their ethnic identities. British acquisition of Penang, Melaka, and Singapore - the Straits Settlements from 1786 to 1824 started a steady inflow of Indian labour. This consisted of traders, policemen, plantation labourers and colonial soldiers (see sepoys). Apart from this there was also substantial migration of Indians to work in the British colonial government, due to their general good command of the English language.

The establishment of the plantations and the need for mass labour led to an influx of Indian migrants working under the indenture Kangani system in the 19th and early 20th century. Some, after the Kangani system ended in the early 20th century, also paid for their own passage to Malaya. These migrant workers were primarily Tamils (around 80%), with some Telugus, Malayalis as well as Bengalis from eastern India and Punjabis from western India. The Tamil migrants were primarily from Tamil Nadu. These workers were distinct from the commercial and educated group of urban Indians, who were often Tamils, Telugus, Malayali, Punjabis, and Bengalis. The Gujaratis, Sindhis and Marwaris arrived as "passenger Indians" much like in other British colonies. These urban Indians may be Hindus, Christians, Sikhs or Muslims. The Sikhs mainly worked in the police force, while other northern Indians were involved in business. The Malayalees, Ceylonese and Christian Tamils may be involved in government and private white-collar work, the Chettiar in money-lending or finance, while the Vellalar and Muslim Tamils may be in various kind of businesses.

The Indian population in pre-independence Malaya and Singapore was predominantly adult males who were single or with family back in India and Sri Lanka. Hence the population fluctuated frequently with periods of immigration to Malaya and periods of exodus of people back to India. As early as 1901 the Indian population in the Straits Settlements and the Federated Malay States was approximately 120,000. By 1931 there were 640,000 Indians in Malaya and Singapore and they even outnumbered the native Malays in the state of Selangor that year.