An in situ field experiment was conducted to study the effects of simulated nitrogen deposition on soil polyphenols, tannin and soluble sugar in Cunninghamia lanceolata plantation (CUL), Cinnamomum chekiangense (CIC), and Castanopsis fabric (CAF) natural forests in Wanmulin Nature Reserve in Jianou of Fujian Province. Three nitrogen levels were installed, i.e., CK (0 kg/(hm2·a)), low N (30 kg/(hm2·a)), and high N (100 kg/(hm2·a)). The results showed that soil polyphenols was highest in CUL while lowest for tannin and soluble sugar, which all had significant difference compared to both CIC and CAF. Soil polyphenols content in CUF and CAF decreased with nitrogen deposition, and in CIC it significantly decreased by 49.4% at LN only. Soil tannin content had been significantly decreased by 43.5%, 70% and 79.5% in CUL, CIC and CAF at LN compared to CK, respectively. However, it was decreased only for broadleaf soil under HN. An increase of 48.8%, 19.2% and 19.8% was found due to nitrogen deposition for soil soluble sugar in CUL, CIC and CIC at LN, respectively. The effects of N addition on litter polyphenols, tannin and soluble sugar in 3 forest litters were not significant.