Radiofrequency catheter ablation therapy aims to generate ablation lesions on the cardiac tissue surface to interrupt or adjust the transmission of the abnormal electrical signals. Forcing the catheter contact with the cardiac tissue surface exerts a direct force on the tissue to transfer heat energy to a target tissue. Excessive force might be overheating and perforating the heart tissue's surface, whereas deficient force might limit the ablation lesion to insufficient dimensions. Thus, the effects of catheter contact force in generating effective lesions and its part of the ultimate success of a radiofrequency catheter cardiac ablation procedure. Against this backdrop, the purpose of this study was to investigate the effect of catheter contact force on biophysical properties of the ablation lesion formation in radiofrequency catheter cardiac ablation. The eight contact force levels (2, 4, 6, 10, 15, 20, 30, and 40 gf) were applied to the heart tissue surface at the perpendicular orientation and repeated six times at each contact force. And then, lesion surface diameter, lesion width diameter, and lesion depth were measured. The results revealed that the catheter contact force has a significant correlation (P < 0.0001) with lesion surface diameter, lesion width diameter, lesion depth, and lesion volume. When contact force was increased, all ablation dimensions also increased. This current in vitro study demonstrated a substantial impact of the catheter contact force on the ablation lesion formation's biophysical properties in radiofrequency catheter cardiac ablation.