This study aimed to verify the relationship between perceived exertion (session-RPE) and heart rate (HR) methods when quantifying internal training loads in different judo training sessions. Nine male judo athletes performed two training sessions lasting 60 min with a 48 h interval between them: (1) randori and (2) technical–tactical. The internal training load was quantified through the session-RPE (CR 0–10) and the HR methods, as suggested elsewhere (Banister’s and Edwards methods). The Pearson’s linear correlation was used to verify the relationship between session-RPE and HR methods (p < 0.05). A significant positive correlation was found between session-RPE and HR method as suggested by Banister’s (r = 0.93; p < 0.001) or Edwards methods (r = 0.81; p = 0.007) in randori session. Accordingly, session-RPE was also correlated with HR of Banister’s (r = 0.90; p = 0.001) and Edwards methods (r = 0.81; p = 0.008) in technical–tactical session. Results of the present study suggested that the session-RPE may be reliable to quantify training load during judo training randori and technical–tactical when compared to different HR methods.