The invention relates to a method and a device for detecting an in-vehicle environment and response as well as an automobile. The method for detecting the in-vehicle environment and response comprises the following steps: when a passenger is detected to be in a vehicle, detecting in-vehicle oxygen content and in-vehicle temperature; comparing the detected in-vehicle oxygen content and in-vehicle temperature with an oxygen content safety threshold and a temperature safety threshold respectively, and judging quality grade of the in-vehicle environment according to a comparison result; and according to the quality grade of the in-vehicle environment, triggering a corresponding response operation. The method and device which are provided by the invention have the advantages that factors influencing life safety of the passenger are detected more comprehensively, a more direct and effective response mode is carried out, and cost is relatively low.