Canada has a growing and diverse immigrant population due to various immigration acts since the 1970s, and it has ever since remained in an ascending order. Canadian immigration policy has been shaped by two principal imperatives: demography and economics; felt-need to populate the vast empty geographical expanse and/or need for young and preferably educated and skilled immigrants to work the economy. In the period after the Second World War, economic needs have largely determined official policy towards immigration. As Canada is becoming an aging society, in the last several decades, both demography and economics led to be liberalized the immigration policies. After 1970s, the huge migration from non-European countries had heightened the ethno-cultural diversity; it created numerous issues among immigrant groups and Canadian mainstream society and its institutions, and prevailing state laws. First segment of the article briefly highlights immigration history of Sikh and Muslim communities in Canada. Second explores the issues of Sikh and Muslim communities in Canada under the state-sanctioned policy of multiculturalism. Third traces the challenges to both specified groups in the aftermath of 9/11 events. Last concludes all parts of study.