A method, a device and a storage medium for processing a communication service in a circuit switch domain are provided. The method may include: judging, when a communication service being currently processed by a communication terminal is a voice call service or a short message service in a circuit switch domain, whether a switching condition for switching the communication service onto a real-time communication tool in a packet switch domain of the communication terminal is met; if it is met, switching the communication service onto the real-time communication tool in the packet switch domain of the communication terminal.