Abstract: In order to realize wide-narrow row rice transplanting, the eccentric gears and eccentric-modified gears were used to the walking-type rice transplanting mechanism, and transmission case was designed to satisfy the seedlings needle track and pose of wide-narrow row rice transplanting mode in this paper. Its structural characteristics and working principle were illustrated and kinematical analysis models were set up. Computer aided analysis, simulation and optimization program were compiled, and structural parameters of the transplanting mechanism were optimized, which satisfied the working requirements of walking-type rice transplanter. 3D design of the transplanting mechanism was accomplished, and virtual prototype test was finished in ADAMS and physical prototype was developed, and then field test was accomplished. The results were as follow: wide row was 403 mm, and narrow row was 197 mm. The transplanting mechanism can meet the working requirements of wide-narrow row walking-type rice transplanter.