The investigation on the heat transfer of fluid flow through passage with non-circular cross-sections with jet-streams is carried out. The following equation for the heat transfer on this research is obtained. α_a=0.066λ/(d_2-d_1){(r_<max>^2-r_1^2)/r_1(r_2-r_1)(1.04-0.034Z/D)・(d_2^2-d_1^2)/Dd_1}^<1/1.3・(D/Z)<0.052>・(l/d_2-d_1)<-0.231>・(i/e)<-0.538>・P_r^<0.62>・R_e^<1/1.3> The results of this theoretical analysis is shown to be in good agreement with that of the experimental results.