Here is a list of the world's largest islands. Don't forget that Australia is considered a continent, not an island (looks like a big island to me!). Australia is about 3.5 times bigger than the Greenland, which is considered to be the largest island in the world.

#	Island	Country	Area (sq. km)	Ocean
1	Greenland	Denmark	2,175,600	Arctic
2	New Guinea	Papua New Guinea	792,540	Pacific
3	Borneo	Indonesia	725,459	Pacific
4	Madagascar	Madagascar	587,044	Indian
5	Baffin Island	Canada	507,454	Arctic
6	Sumatra	Indonesia	427,305	Indian
7	Honshu	Japan	227,415	Pacific
8	Great Britain	United Kingdom	218,078	Atlantic
9	Victoria	Canada	217,291	Arctic
10	Ellesmere	Canada	196,237	Arctic
11	Celebes	Indonesia	178,710	Indian
12	South Island	New Zealand	151,010	Pacific
13	Java	Indonesia	126,651	Pacific
14	Cuba	Cuba	114,525	Atlantic
15	North Island	New Zealand	144,051	Pacific
16	Newfoundland	Canada	108,858	Atlantic
17	Luzon	Philippines	105,879	Pacific
18	Iceland	Iceland	103,002	Atlantic
19	Mindanao	Philippines	95,247	Pacific
20	Novaya Zemlya	Russia	90,650	Arctic
21	Ireland	Ireland	84,431	Atlantic
22	Hokkaido	Japan	78,073	Pacific
23	Hispaniola	Haiti/Dominican Republic	76,483	Atlantic
24	Sakhalin	Russia	76,405	Pacific
25	Banks	Canada	70,015	Arctic
26	Tasmania	Australia	67,801	Pacific
27	Sri Lanka	Sri Lanka	65,610	Indian
28	Devon	Canada	55,247	Arctic