Most nationalities can enter without a passport.
Nationals from the following countries require a visa before arriving;
Afghanistan, Angola, Bangladesh, Bhutan, Burkina Faso, Burundi, Cameroon, Central African Republic, China, Colombia, Comoros, Congo Democratic Republic, Congo Republic, Cote D'ivoire, Djibouti, Equat. Guinea, Eritrea, Ethiopia, Ghana, Guinea-Bissau, India, Liberia, Mali, Mozambique, Myanmar, Nepal, Niger, Nigeria, Pakistan, Rwanda, Serbia & Montenegro, Sri Lanka, Taiwan, United Nations (Laissez Passer) and Western Sahara
Visa Requirements for visiting Malaysia.
Malaysian embassies
Foreign missions in Malaysia