The invention discloses a method and a device for controlling a heat collecting unit. The method comprises the steps of receiving a control command for controlling the heat collecting unit, wherein the control command at least comprises one of the following commands: a heat collecting unit starting command, a heat collecting unit turning-off command and a heat collecting unit switching command; and automatically controlling the state of each valve corresponding to the control command according to a preset execution sequence when an execution condition of the control command is met. According to the invention, the workload of operators can be reduced, the reliability of the system is improved, misoperation is avoided, switching can be completed through one operation, the operation process is simplified, the operation efficiency is improved, and steam operation parameters are optimized.