Background: Laparoscopic intracorporeal suturing is important to master and competence should be ensured using an optimal method in a simulated environment before proceeding to real operations. The objectives of this study were to gather validity evidence for two tools for assessing laparoscopic intracorporeal knot tying and compare the rater-based assessment of laparoscopic intracorporeal suturing with the assessment based on simulator metrics. Methods: Twenty-eight novices and 19 experienced surgeons performed four laparoscopic sutures on a Simball Box simulator twice. Two surgeons used the Intracorporeal Suturing Assessment Tool (ISAT) for blinded video rating. Results: Composite Simulator Score (CSS) had higher test-retest reliability than the ISAT. The correlation between the number performed procedures including suturing and ISAT score was 0.51, p<0.001, and 0.59 p<0.001 for CSS. We found an inter-rater reliability (0.72, p<0.001 for test 1 and 0.53 p<0.001 for test 2). The pass/fail rates for ISAT and CSS were similar. Conclusion: CSS and ISAT provide similar results for assessing laparoscopic suturing but assess different aspects of performance. Using simulator metrics and raters’ assessments in combination should be considered for a more comprehensive evaluation of laparoscopic knot-tying competency.