Crystal structures and magneto-optical properties of $(Mn_{0.5-Z}Sb_{0.5+Z})_{100-y}Pt_y$ (0<z<0.03, 4.1<y<21.7) and $(Mn_{0.5-Z}Sb_{0.5+Z})_{100-y}Ag_y$ (0<z<0.08, 2.1<y<11.3) alloy films prepared by RF magnetron sputtering have been studied by X-ray diffractometer, vibrating sample magnetometer, torque magnetometer, Kerr loop tracer. The crystal structure of MnSbPt and MnSbAg films annealed at 300 $^{circ}C$ are C1b-type with fcc and NiAs-type with hcp, respectively. The MnSbAg films have a texture which the c-axis orientation is perpendicular to the film plane by annealing at 300 $^{circ}C$ for less than 3 hours. The perpendicular anisotropy constants of the $Mn_{47.4}Sb_{47.5}Ag_{5.1}$ film annealed at 300 $^{circ}C$ for 3 hours are $K_1=6.6{ imes}10^5 ; erg/cm^3;and;K_2=1.9{ imes}10^5; erg/cm^3$. The Kerr rotation angle of MnSbPt films increases but that of MnSbAg film decreases by decreasing incident wavelength within the range of 700$leq$ λ$leq$1000 nm. High polar Kerr angles of 1.7$^{circ}$ (λ =700 nm) and 0.6$^{circ}$ (λ =1000 nm), 0.2$^{circ}$ (λ =700 nm) and 0.97$^{circ}$ (λ =1000 nm) have been obtained from $Mn_{41.1}Sb_{44,9}Pt_{14.0}$ and $Mn_{47.4}Sb_{47.5}Ag_{5.1}$ alloy films, respectively.