We conceptualized and developed a measure of right-wing protective popular nationalism (RWPPN) – a specific form of popular nationalism where people seek to protect the national culture from outgroup influences. RWPPN is derived from a sociological analysis of right-wing popular nationalism in Australia and is theoretically related to several key psychological constructs, including right-wing authoritarianism (RWA), social dominance orientation (SDO), and symbolic threat. We conducted two surveys using nationally representative samples of Australian citizens. In study 1 (<i>n</i> = 657), participants completed measures of RWPPN and related constructs. Exploratory and confirmatory factor analysis resulted in a 10-item scale. Construct validity was tested and confirmed across divergent, convergent, predictive, and concurrent validation domains. Additional convergent validation with RWA and SDO was tested in study 2 (<i>n</i> = 316). Together, RWPPN was found to relate to expressions of national identity, prejudice, perceived outgroup threat, opposition to multiculturalism, and aggressive tendencies toward ethnic minorities. These effects remained significant when controlling for nationalism (measured as a concern for national superiority) and blind patriotism. In study 2, the effect on aggressive tendencies held when controlling for RWA and SDO and RWPPN mediated the relationship between RWA and aggressive tendencies. Reflecting the conservative nature of Australian popular nationalism, RWPPN correlated with right-wing political alignment. The research was conducted in Australia, but given the rise in right-wing populism internationally, RWPPN may be a phenomenon in other countries. Therefore, this paper offers a new construct and scale to investigate it in Australia and internationally.