The Nd:YAG ceramic laser at 670 nm was studied by means of dispersion prism and KTP intracavity-frequency-doubling. We designed and optimized the cavity parameters by MatrixLaser software based on the standard ABCD ray propagation matrix. By using the laser diode arrays side-pumped Nd:YAG ceramic crystal with Nd doping concentration of 1.1at% and dimension of Φ3×50 mm, the Nd:YAG ceramic laser at 670 nm was realized. Under repetition rate of 1 000Hz and single pulse pumped energy of 144 mJ, the output energy of 5.1mJ at 670 nm is obtained. The optic-optic efficiency is 3.54%. The results not only formed the basis for the further development of the high power and high efficiency ceramic red laser, but also provided a great prospect for the high power ceramic red laser in the field of medical treatment, color display and other areas of application.