Apis dorsata are important pollinators, while their honey is the most popular for consumption in Asia. Although they have an aggressive and very thorough grooming behavior, ectoparasitic mites that can act as disease vectors have been reported. Here, the presence of mites on different developmental stages of A. dorsata was investigated in three hives in Samutsongkram province in February, 2021 to reveal the health status of A. dorsata in Thailand. No ectoparasitic mites were observed under stereo and compound light microscopy based examination of 150 adult bees (50 bees/hive). In contrast, phoretic mites were found on the bee’s thorax, principally the legs of pair no. 3. Morphological analyses, including scanning electron microscopy, placed the mites in the order Oribatida, and possibly Forcellinia faini, but this awaits molecular confirmation. Prevalence of adult bees with phoretic mites from hive no. 1, 2, and 3 was 32%, 20%, and 30%, respectively, with a range of 0–10 mites per bee. No mites were observed on non-adult stadia. No Paenibacillus larvae, which causes American foulbrood disease, was detected in the mites by multiplex PCR using specific primers for 16S rRNA of bacteria and cytochrome b (cytb) for Apis spp. under an optimized PCR condition. Rather the bacterial amplicon showed a 91.5% nucleotide sequence identity to Lactobacillus fermentum (probiotic bacteria). The ecologic impact of this relationship between phoretic mites, probiotic bacteria, and honeybees, as well as the effect of mites on pollination by A. dorsata, needs to be determined.