Countries have adopted different laws, policies, and practices that allow immigration officers to request in certain cases DNA tests to confirm biological relationships in the context of family reunification. In Canada, Citizenship and Immigration Canada has adopted a policy of suggesting DNA testing only as a last resort in cases where no documentary evidence has been submitted or where the evidence provided is deemed unsatisfactory. However, in practice, there have been concerns on the increasing use of DNA tests in family reunification processes of nationals from certain regions including Africa, Asia, and Latin America. Moreover, the Immigration and Refugee Protection Regulations (IRPR) presents a biological definition of family as a determinant of parenthood in the context of family reunification that is inconsistent with the psychosocial definition used in provincial family laws. Although there are cases that can justify the request for DNA tests, there are also significant social, legal, and ethical issues, including discrimination and unfair practices, raised by this increasing use of genetic information in immigration. This policy brief identifies points to consider for policymakers regarding the use of DNA testing in Canadian family reunification procedures. These include (1) the need to refine the policy of “using DNA testing as a last resort” and its implementation, (2) the need to modify the definition of “dependent child” under the IRPR to reflect the intrinsic reality of psychosocial family ties, and (3) the importance of conducting more research on the use of DNA testing in other immigration contexts.