Output characteristics of a tunable fiber ring laser are studied both by theoretical modeling and by experimentation. Dependencies of laser output power on lasing wavelength, pump power, erbiumdoped fiber (EDF) length, output coupling ratio, and intracavity loss are demonstrated by using a simple theoretical model. It is shown that a wide tunable range over 130nm (i.e.1500—1630nm) can be obtained through parameter optimization. As a result, the laser with a tunable range up to 100nm, high output power, and high signaltonoise ratio in most of the tunable range has been achieved in experimentation. The experimental data are in good agreement with the theoretical modeling results.