In order to elucidate the distributions of rare earth elements in fern (Dicranopteris dichotoma Bernh.) and the photosynthetic characterizations of Dicranopteris dichotoma, the concentrations and fine location of rare earth elements in Dicranopteris dichotoma in light, heavy rare earth elements mine and non mining area in Longnan county of Jiangxi province, China were throughtly investigated by means of inductively coupled plasma-mass spectrometry (ICP-MS), transmission electron microscopic (TEM), and energy-dispersive X-ray microanalysis (EDAX). The photosynthetic characterizations of Dicranopteris dichotoma in natural conditions and non rare earth elements hyperaccumulator Cucumber (Cucumis sativus Linn) treated with high concentrations LaCl3 also had been studied. This book featured as exploring mechanisms of photosynthetic characterization of fern at different conditions as well as fine location of rare earth elements in fern cell.