The outbreaks of invasive plant species can cause great ecological and agronomic problems through aggressively competing for environmental resources that could be otherwise utilized by other desirable species. Thus, it is crucial for detecting small infestations before they reach a sig-nificant extent that can cause ecological and economic damages over a large geological area. Re-mote sensing is a proven method for mapping invasion extent and pattern based on geospatial imagery and indicated great repeatability, large coverage area, and lower cost compared with tra-ditional ground-based methods before. We investigated the feasibility and performances of adopt-ing multispectral satellite imagery analyses for mapping infestation of musk thistle (Carduus nu-tans) on native grassland, crop field, and residential areas in early June using spectral angle map-per classifier. Our results showed an overall classification accuracy of 94.5%, indicating great po-tential of using moderate resolution multispectral satellite-based remote sensing techniques for musk thistle detection over a large spatial scale.