The utility model discloses a filter for a beam dyeing machine. The filter comprises a filter drum, wherein the filter drum is detachably arranged in a circulated liquor storage cylinder, the filter drum is of a drum structure, an opening is formed in one end of the filter drum, the other end of the filter drum is sealed, a plurality of filter holes are uniformly formed in the filter drum, and the size of each of the filter holes is smaller than the minimum size which enables fiber filaments to pass through. According to the filter disclosed by the utility model, the size of each of the filter holes in the filter drum is set to be smaller than the minimum size which enables the fiber filaments to pass through, circulating filtration on dyeing liquor can be carried out by utilizing the filter drum, the dyeing liquor can be sprayed to the surface of fabric in a pressure cooker of the beam dyeing machine for dying through the circulated liquor storage cylinder, a chemical pump and a dyeing liquor spray nozzle after being filtered, the fabric is dyed by adopting the dyeing liquor which is in circulating filtration, smaller-size impurities such as broken fiber filaments on the fabric are prevented from being left on the surface of the fabric along with continuous circulating spraying of the dyeing liquor, the surface quality of the fabric is ensured, and the cleaning procedures are reduced.