Ovariohysterectomy (OHE) is one of the most common surgeries in veterinary medicine. Although this surgical method has several advantages, it can alter the function of various organs such as heart. The present study investigated the effect of OHE on cardiac functions using M-mode echocardiography. A total of 10 healthy adult domestic short-haired cats were enrolled in the current study. Fractional shortening (FS) and ejection fraction (EF) percentages along with cardiac output (CO) were measured through the right parasternal approach in papillary muscle level view. Moreover, the levels of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) were measured by enzyme-linked immunosorbent assay before OHE (D0) as well as 10 (D10), 20 (D20) and 30 (D30) days after OHE. The results of this study showed that the mean FS and EF decreased on all days of the study. The FS reduction was significant between D10 and D30 and EF changes were significant between D10 and D20. The means of CO increased significantly on D0 compared to the D10. After D20, CO reduced until the end of the study. Mean concentrations of LH and FSH increased on all research days; but, the changes were significant until D20. Despite the negative effects of OHE on myocardial function, there was no significant correlation between hormonal levels and echocardiographic findings after OHE in this study.