Background Large-scale emergencies hurt the chronically ill immensely. Improving personal emergency preparedness is an effective means to protect themself. Our objective is to evaluate the emergency preparedness level and its influencing factors among patients with chronic diseases in China. Methods A paper-based self-administrated questionnaire collected data. Descriptive statistics and univariate analysis were used to illustrate the chronically ill's general characteristics and preparedness level. Regression models were constructed to identify influencing factors of preparedness. Results A total of 771 samples were included. Only 23% of respondents prepared three days of water, three days of food, available flashlights, and available radios. 50% were equipped with three-day prescription drugs. Patients with chronic respiratory diseases or cancer were less prepared (p < 0.01). Patients who were never married or married (compared with widowed, divorced, or separated); had junior high school degrees (compared with a college degree and above); had monthly household incomes of more than 10,000 yuan; suffered from two or above chronic diseases, often and rarely discussed emergencies with families (compared with never); perceived learning emergency-related information as essential; participated in emergency drills; believed their families have prepared; and had high levels of mental health are more likely to have the four preparations. Factors related to higher levels of prescription drug reserve include owning junior high school or high school degrees, having two or above chronic diseases, being sick for five to nine years (compared to less than or equal to one year), being interested in gathering information about the emergency response, and perceived learning emergency-related information is crucial.​ Conclusion Patients with chronic diseases have a low level of emergency preparedness. Public health officials should formulate tailored policies, information, and intervention measures that target chronically ill patients to improve their emergency preparedness, particularly those with low income, low mental health, divorce, widowhood, or separation.