Magnetic helical micro/nano-robots is inspired by the structure of the Escherichia coli (E. coli) bacterium. Since low-power magnetic fields are harmless to cells and tissues, magnetic helical micro/nano-robots are promising as a medical tool especially for in vivo applications. One of the uses of micro/nanorobots is to deliver drugs to cancerous tumors with minimal side effects. The present study models the swimming motion of the magnetic micro-robot inside a microchannel filled with blood, as a non-Newtonian fluid, using the Stokes equations. The nonlinear coupled equations are solved by a finite element method based software. The results indicate that increasing the number of helix turns, with a cut-off value, causes the terminal velocity of the microswimmer to increase. It is also shown that increases in the helix pitch causes the terminal velocity of the microswimmer to increase. Moreover, studies on cylindrical, spherical, and elliptic microswimmer heads indicated that the elliptic head has the minimum transverse displacement which is almost negligible.