The invention provides a pyrimidyl indole derivative and a preparation method thereof as well as the application of the pyrimidyl indole derivative in preparation of an antitumor drug. According to the pyrimidyl indole derivative and the preparation method thereof, and the structural feature of a pyrimidyl indole compound, on the basis of a 3-substituted pyrimidine-1H-indole parent nucleus, different pharmacophores and alkyl chains with the tail ends connected with the different pharmacophores are introduced, so that the pyrimidyl indole derivative with antitumor activity is obtained, and hasa structural formula as shown in the specification. An experiment of the invention shows that the pyrimidyl indole derivative provided by the invention and a pharmaceutically acceptable salt thereof have high inhibition activity to various tumor cell lines and can be applied to preparation of the antitumor drug.