Human-mediated species introductions have greatly contributed significantly to the current global alteration of the biosphere, with many invasive species rapidly expanding their geographic ranges, leading to changes in biodiversity and disruptions of ecosystem functioning. With a modified SDM that considers both extensive data coverage and the distance to previously already occupied areas, we show continued shifts and expansions of geographic ranges of two globally invasive tephritid pest species Bactrocera dorsalis and Ceratitis capitata). Both tephritid pests are still expanding globally, with their geographic ranges estimated to have expanded by 65% and 22% in the past three decades. The potential future geographic distributions of B. dorsalis and C. capitata under four scenarios of Representative Concentration Pathways (RCPs) for 2050 highlighted some key changes when compared to their current occurrences. Under all four RCPs by 2050, the potential geographic distribution of C. capitata was predicted to shrink by 5-14%, while the distribution of B. dorsalis was predicted to increase by 12-15%. Under different climate scenarios for 2050, B. dorsalis could experience a notable poleward expansion with increasing connectivity in its future geographic distribution. The two tephritids will continue to co-occur in Africa, with B. dorsalis experiencing higher suitability in most regions where they overlap. Climate changes were estimated to contribute more, than non-equilibrial invasion expansion, to changes in the geographic ranges of the two tephritid pests. The forecasted potential geographic distributions could enhance regional biosecurity preparedness in future climates and mitigate proactively the economic loss from these fruit fly pests.