There is a thermodynamic model to determine structure H (sH) hydrate stability conditions i.e the Klauda-Sandler model, which was typically used for water-immiscible or slightly soluble sH hydrate formers in the presence of various help gas. However, some sH clathrate hydrate formers are soluble in water such as 1-methylpiperidine and 2-methylpiperidine. In this study, the Klauda-Sandler model was used to model sH hydrate stability conditions for 1-methylpiperidine and 2-methylpiperidine with methane as a help gas. The Peng-Robinson equation of state is used for the calculation of the fugacity of the help gas.The aqueous phase behavior containing these components is modeled using the NRTL activity coefficient model. This model show errors of less than 2% which shows that the Klauda-Sandler model result is in acceptable agreement with the experimental data. Nevertheless, AAD% for 1-methylpiperidine is 0.0056% while it is 1.2% for the other component that implies the accuracy of the Klauda-Sandler hydrate model for 1-methylpiperidine.