The effective spin-rotational Hamiltonians of 2Σ12 and 2Π12 states of mercuric fluoride ( 202Hg 19F) molecule are constructed, and the hyperfine structures, Stark shift in external electric field and Zeeman shift in external magnetic field of ground state are calculated. The variation of the g-factor in external electric field is simulated with the first-order perturbation theory. The possibility of using the N=1, J=1/2, F=1, MF=±1 state of 202Hg 19F molecule to measure the electron electric dipole moment is discussed (N, J and F are quantum number of angular momentum).