Background: The COVID-19 pandemic forced higher education institutions globally to transition abruptly from traditional classroom learning (TCL) to online distance learning (ODL). Understanding students' perception and achievements is crucial for enhancing learning outcomes. Aim: This study aimed to examine the scholarly achievements and learning perceptions of nursing students who learned by online learning with the adoption of the principles of integrated learning theory compared to those who learned through classroom-based learning, as well as assess students' readiness for the online learning. Methods: A quasi-experimental research design was employed, involving 649 bachelor's nursing students divided into study and control groups. The study group learned selected courses via ODL, incorporating principles from integrated learning theory, while the control group received TCL for the same courses. Two adopted tools was utilized to measure students' perceptions and students' readiness while scholarly achievement was evaluated through GPA. Results: No significant statistical difference was found in overall student learning perceptions between the study and control groups (p = 0.13) with a small clinical effect size (-.082). While there was no significant difference in GPA for clinical courses (p = 0.099), the study group achieved significantly higher GPAs for theoretical courses (p = 0.008). For the students' readiness for ODL the study group demonstrated neutral (moderate) level, with an overall weighted mean of 3.36 ± 0.86. Conclusions: Despite the unplanned transition to ODL during COVID-19, TCL and ODL were perceived similarly by the students when incorporating ODL with the principles of integrated learning theory. ODL positively enhance students' GPA in theoretical courses, but had no significant effect on clinical courses. This suggests that ODL cannot fully replace TCL in nursing education, particularly for clinical courses, which require more virtual clinical simulations. Therefore, blended learning may offer a more effective solution.