In the liquid crystal MHPOBC (4-(1-methylheptyloxycarbonyl)phenyl 4‘-octyloxybiphenyl-4-carboxylate), doxyl spin probe was dissolved and ESR spectra were observed in the antiferroelectric and ferroelectric smectic phases. The molecules of the liquid crystal in the tube- and sandwich-type cells were oriented by the static magnetic field before measurements. An anchor effect of the cell surface on the molecules of the liquid crystal was discussed. Angular variation of the spectra was discussed in connection with alignment of the spin probes in the cells and with the structure of the liquid crystal in the smectic phases.