[Aim]  To develop a relatively quick method to detect the sensitivity of Panonychus citri to commonly used insecticides and acaricides in orchards, thereby optimizing the use of these chemicals. [Methods]  The toxicity of 10 insecticides and acaricides to sensitive strains of P. citri were determined using the leaf impregnation method. LC₅₀ and LC₉₉ values were calculated using the probability of death method. Using twice the LC₉₉ value as the alternative diagnostic concentration, and setting a corresponding diagnostic concentration gradient for validation experiments, the concentration that achieved 100% mortality was selected as the diagnostic dose. Based on the toxicity regression curve and diagnostic dose method, evaluation criteria for pesticide sensitivity for a P. citri diagnostic kit were developed. [Results]  The diagnostic doses of 10 insecticides and acaricides, abamectin, cyflumetofen, bifenazate, etoxazole, spirodiclofen, spirotetramat, progargite, pyridaben, chlorpyrifos and matrine, were 550, 400, 700, 650, 3 300, 2 000, 850, 350, 550 and 950 mg/L, respectively. The diagnostic kit classifies populations in terms of resistance as follows; those with a mortality rate ≥ 95% are classified as sensitive, those with a mortality rate between 88% and 95% are classified as having reduced sensitivity, and those with a mortality rate < 88% are classified as resistant. [Conclusion]  The diagnostic kit developed in this study can quickly assess the sensitivity of P. citri populations to insecticides and acaricides in the field by measuring the mortality rate. This provides a way to quickly select the most effective insecticides and acaricides for controlling a given P. citri population at a particular point in time.