Rich and unique fungal resources exist in tropical and subtropical mangrove forests in the coastal intertidal zone. Fungi are involved in the decomposition of organic matter and regeneration of inorganic nutrient. They can degrade pollutants in the marine environment, promote marine self-purification, and play an important role in the marine ecosystem. The plant root system is rich in microbial species and biomass. However, research on the fungal ecological status in mangrove roots is limited. This study was conducted in the core zone of Zhanjiang Mangrove National Nature Reserve, Guangdong Province, namely Gaoqiao Mangrove Reserve with the area of 700.1 hm² (E 109 °40 ‘-110 °35',N 20 °14 ‘-21 °35') extending linearly along the 27 km long coast. Rhizosphere (0 cm to 2.5 cm) and non-rhizosphere (2.5 cm to 10 cm) fungal and environmental samples were collected from six species of mangrove communities to analyze the affect of mangrove root on fungal abundance and species composition and to examine the relationships of fungi with environmental factors. Results showed that a total of 35 different morphology colonies appeared in the culture medium, and 5 genera and 11 species of fungi were identified by fungal morphological identification technology. These species were Aspergillus zhaoqingensis, Aspergillus japonicus var. japonicus, Aspergillus carneus, Cladosporium sphaerospermum, Aspergillus niveus, Trichoderma atroviride, Cladosporium pallidum, Talaromyces flavus, Cladosporium cladosporioides, Penicillium minioluteum, and Penicillium variable. The fungal abundance in the six species of mangrove rhizosphere was 3.38 × 10³ cfu/g to 10.94 × 10³ cfu/g dry soil, and the fungal abundance in non-rhizosphere was 4.12 × 10³ cfu/g to 8.78 × 10³ cfu/g dry soil. According to the plate count of fungi, the R/S ratios of the six mangrove species followed the order Bruguiera gymnorrhiza (1.73) > Kandelia candel (1.25) > Sonneratia apetala (1.07) > Aegiceras corniculatum (1.02) > Rhizophora stylosa (0.71) > Avicennia marina (0.47). The abundance and species of rhizosphere fungi in A. corniculatum, B. gymnorrhiza, S. apetala, and K. obovata forests were higher than those in non-rhizosphere fungi, whereas those in R. stylosa and A. marina forests were the opposite. This finding indicated that the former four species promoted rhizosphere fungal growth, whereas the latter two species inhibited rhizosphere fungal growth. The species number of rhizosphere fungi in the six mangrove species was 7-19, whereas that of non-rhizosphere fungi was 8-13. A. corniculatum, B. gymnorrhiza, S. apetala, and K. obovata promoted rhizosphere fungal growth, whereas R. stylosa and A. marina inhibited rhizosphere fungal growth. Overall, the fungal species number in the mangrove forest was much higher than that outside the forest, which indicated that the coverage of mangrove plants promoted the species diversity of fungi. The fungal abundance in rhizosphere showed a significant negative correlation with total organic carbon (TOC), whereas the species number in non-rhizosphere fungi was significantly correlated with NO₃-N, which illustrated that TOC in rhizosphere may contain certain substances that can restrain fungal growth. While in the non-rhizosphere, root exudates of mangrove plants had less influence on fungi growth. In general, root exudates of mangrove plants have certain effects on the quantity and species number of rhizosphere microorganisms.