The invention belongs to the vacuum metallurgy area, in particular to a method of vacuum-induction melting TiAl-based alloys. The CaO-based crucible refractory material with good thermodynamic stability and low hydration speed is as the crucible material for vacuum-induction melting; the melted alloy is the TiAl-based alloy with high chemical activity; the melting frequency is 2000 to 5000Hz. Thedetailed operation technology is: Ti, Al and other raw materials are put into the crucible at a time; the raw materials are melted in high vacuum; after all raw materials are melted, the temperature is raised to be above the melting point of 30 to 200DEG C, and cast ingots or cast parts are finally cast. The invention is applicable in melting of the TiAl-based alloys of high chemical activity; the electromagnetic stirring brings even alloy chemical components; and the content of impurity of cast ingots or cast parts can be effectively reduced by increasing melting frequency when the melting frequency is 2000 to 5000 Hz, so as to improve the quality of cast parts.