This study aims to examine the feasibility of applying a complex dynamical analysis method to electrogastrography (EGG). We analyzed EGGs using the maximum Lyapunov exponent (MLE), which is one of the indices of the chaotic characteristics of sequential biosignals. In the result, the chaotic process is considered to generate the EGGs irrespective of their embedding delay and dimension. The MLE decreased with an increase in the embedding dimension for a particular embedding delay. In nonlinear analysis, indices are required to be considered for calculations involving a constant embedding dimension and delay.