The invention relates to a crystalline methyl carbamate compound, namely a crystal form of N-[(2S)-1-[(2S)-2-{4-[7-(4-{2-[(2S)-1-[(2S)-2-[(methoxycarbonyl)amino]-3-methylbutyryl]pyrrolidin-2-yl]-1H-imidazol-4-yl}phenyl)-2H-1,3-benzodioxan-4-yl]-1H-imidazol-2-yl}pyrrolidin-1-yl]-3-methyl-1-oxybutan-2-yl]methyl carbamate dihydrochloride, a pharmaceutical composition containing the crystal form, anda use of the crystal form in preparation of drugs in treatment of hepatitis C virus.