<p>This study aimed to explore the effect of continuous care based on the information-knowledge-attitude-practice (IKAP) theory in patients with diabetic macular edema (DME). A total of 130 patients with DME, admitted to the Ophthalmic Center of a Grade-A tertiary hospital in Weifang between January and December 2022, were enrolled and randomly assigned to a control group (<i>n</i> = 65) or a research group (<i>n</i> = 65) using the random number table method. The control group received routine discharge follow-up guidance, whereas the research group received continuous care based on the IKAP theory in addition to routine care. Illness perception, self-management ability, quality of life, and visual improvement were compared between the two groups before and three months after the intervention. After three months of intervention, the illness perception score in the research group was significantly lower than in the control group. Conversely, self-management ability and quality-of-life scores were significantly higher, and the effective rate of visual improvement was superior in the research group. All differences were statistically significant (<i>P</i> &lt; 0.05). Continuous care based on the IKAP theory may improve illness perception, enhance self-management ability, and promote visual acuity and quality of life in patients with DME.</p>