To evaluate the accuracy of home self-monitoring portable blood glucose meters, we analyzed the current problems of patients using portable blood glucose meters and put forward reasonable suggestions. A self-designed questionnaire was used to survey 142 patients and 132 healthcare professionals. The questionnaire consisted of 16 items with an overall score ranging from 1 to 13 (with a higher score indicating better experience). The study included adult patients with diabetes mellitus type 1 or type 2. The patients’ awareness rate for standardized use of portable blood glucose meters at home was at 31.42%. Specifically, awareness of blood collection specifications was at 15.85%, standardized operation at 42.53%, and accuracy of results at 0%. A significant majority (81.69%) scored between 0 and 5 points in home blood glucose meter use, with knowledge and practice scores consistently below 3 points. Notably, no patients conducted a formal comparison of various meters. Despite this, their confidence level in the portable blood glucose meter results was as high as 71.1%. Urgent measures are needed to educate patients on proper usage and encourage regular instrument comparisons.