Molybdenum alloys, as high-performance refractory metals, possess significant potential for applications under extreme service conditions, including high temperatures and irradiation environments. Under such conditions, high-temperature creep resistance is a critical performance metric. However, welded joints of molybdenum alloys frequently exhibit substantial degradation in creep properties, which severely limits their structural applications. This review systematically summarizes the mechanisms governing creep strengthening in molybdenum alloy base metals and examines the primary factors contributing to the reduced creep resistance in welded joints. Based on these mechanisms and contributing factors, various strategies for enhancing joint performance reported in domestic and international studies are consolidated. Furthermore, the advantages, limitations, and applicability of current creep testing methods for welded joints are evaluated. Finally, future research directions and challenges in improving the high-temperature creep performance of molybdenum alloy welded joints are discussed.