Tea (Camellia sinensis (L.) Kuntze) is one type of important cash plantsand widely cultivated in the hilly areas of subtropical region of south China.The diurnal variations of net photosynthetic rate (Pn) of tea and its eco-physiological factors were studied with Fuyunzaohao(a tea cultivar) as well as the effects of 7 different fertilization applications on them by using a set of field experiments in Dongxishan tea farmin Baili Chalang (113°19′E，28°33′Nat an elevation of 135m).The diurnal variation of Pn showed two peaks under fine weather conditions, which indicated that there was an obvious phenomenon of midday-depression while the eco-physiological factors exhibited some influence on it. Photosynthetic active radiation (PAR), air temperature (Tl) and concentration of CO2of air (Ca) were dominant factors in field ecosystem, while transpirationrate (Trl), stomatal conductance (Gs) and concentration of CO2in cells (Ci) were dominant physiological factors. The regression and path coefficient indicated that ecological factors, especiallylight and temperature, had the greatest influence on Pn, however, the fertilization applications had little effects on those relatively stable climate factors such as PAR, Tl, Ta and RH. Application organic fertilizer including 100%, 75%, 50% and 25% of full amount of organic material resulted in obvious increase of Trl, Gs and diurnal Pn, the tea plants absorbed and consumed more CO2in comparison with the application of chemical fertilizer, intercropping white clover without fertilization and no fertilization treatments. The clustering analysis of Pn and its 8 main eco-physiological factors suggested that the capability of photosynthesis among the treatments could be divided into 4 groups, e.g. application of 100% and 75% organic fertilizer were on the top class with strongest ability followed by 50% and 25% organic fertilizertreatments, chemical fertilizer and intercropping white clover without fertilization were the next group, and no fertiliztion was the lowest.