The invention discloses an automatic polymer melt filter switching device capable of keeping continuous material flow. The automatic polymer melt filter switching device comprises a flow channel switching mechanism, a rotary filter mesh switching mechanism and a transverse-moving filter mesh switching mechanism; the rotary filter mesh switching mechanism comprises a first base, the first base is provided with a protrusive gear ring portion, a fixing outer gear ring is arranged on the outer cylindrical face of the protrusive gear ring portion, a rotary inner gear ring is rotatably arranged on the outer cylindrical face of the first base, at least m planetary filter mesh frame units are rotatably and symmetrically arranged between the fixing outer gear ring and the rotary inner gear ring ina meshing mode, and m is a positive integer larger than or equal to 2; and the flow channel switching mechanism, the rotary filter mesh switching mechanism and the transverse-moving filter mesh switching mechanism cooperate with one another to do alternate action to complete a filter mesh switching function. According to the automatic polymer melt filter switching device capable of keeping the continuous material flow, a left-right transverse moving mechanism is designed in the radius range of a rotary planetary gear mechanism in an embedded mode, the size is small, and multiple replaceable planetary filter mesh frame units are arranged.