Provided is a conformal intensity-modulated radiation therapy device, comprising: a housing, formed with an accommodating space and a shielding cavity; shielding material, filled within the shielding cavity; a rotary source-carrying body, accommodated within the accommodating space; a shielding rod, accommodated within the rotary source-carrying body; a source body, accommodated at a bottom end of the shielding rod and used for carrying a radiation source; a first driving portion, arranged on the housing and driving the rotary source-carrying body to rotate around a rotary axis thereof so that the radiation source switches between an open source position and a closed source position; a pre-collimation body, arranged at an emission end of the radiation source and comprising a collimation hole, the collimation hole directly facing the radiation source when the radiation source is in the open source position; a shielding door, arranged at the side of the pre-collimation body away from the radiation source and directly facing the radiation source; a multi-leaf collimator, arranged outside the housing and directly facing the shielding door. Also provided is a conformal intensity-modulated radiation therapy system.