The purpose of this manuscript is to present a reliable estimate of the Muslim population and its percentage in each country in Oceania from 1950 till 2020. This data is summarized to be a reference for other studies and discussions related to the Muslim population. The presented data show that the percentage of World Muslim population with respect to the total World population has increased steadily from 17% in 1950 to 26% by 2020. While the total Oceania population increased from 13 million in 1950 to 41 million by 2020, the percentage of Muslims in Oceania increased from 0.2% in 1950 to 1.3% by 2020. Muslims remain well under represented in Oceania, although there are substantial minorities in Australia, New Zealand and Fiji. Accordingly, the total population of Oceania increased from 13 million in 1950, to 41 million by 2020. Therefore, it is the least populated continent in the world. The related Muslim population increased from 0.3% in 1950, to 1.3% by 2020. The results of this paper are summarized in tables and a superscript number is put by a country name representing the source of the percentages. A (year) sign is put next to this number to indicate that the source bases its estimate on official census data and the year the census was conducted. Percentage values are based on the latest available census and reliable estimates. Official censuses were considered in this study to be the most reliable; although official censuses are usually challenged by minorities, whether Muslims or not, claiming that their number is underestimated for various reasons. However, these claims tend to be based on emotions and wishful thinking and not on scientific facts. In addition, residents who are not citizens are not counted in many religious and ethnic censuses. While typically non- citizens do not influence the political life in a country, they do help in establishing and maintaining various religious facilities and activities. Thus, it makes sense to include them in an estimate that inquires about adherents of a certain religion in a country. However, not all censuses inquire on religious adherence, nor are held regularly. Thus, our second source of estimates is Demographic and Health Surveys (DHS) that include data on religion. When no census or Survey is available, we resort to other estimates from reliable sources. The total population estimate for each country and the corresponding annual population growth rate (APGR) since 1950 are based on (UNP). An estimate for the Muslims demographics in the decennial estimates based on these growth rates.