A research has been conducted on the statistical diagnosis of quasi-likelihood nonlinear models based on empirical likelihood estimation. Firstly, the empirical likelihood ratio function of the model has been provided, thus obtaining the empirical likelihood estimation of the model. Then, based on the case deletion model, the first-order approximation formula of parameters is to be derived, with the empirical Cook distance subsequently proposed. Finally, the validity and rationality of the statistical method can be verified by an analysis of a case study.