Introduction: A woman's body experiences numerous physiological and psychological changes throughout pregnancy in order to accommodate the expanding requirements of the growing fetus. These changes can lead to various pregnancy-related health issues like gestational diabetes, and pre-eclampsia. Women who regularly engage in physical activity during pregnancy have a reduced risk of developing those health problems. Pregnant women should have adequate knowledge and a good attitude towards physical activity during pregnancy, which is an essential precursor for practising exercise. Therefore, this study aimed to assess the knowledge and attitude of antenatal mothers regarding physical activity during pregnancy at a tertiary care hospital in Puducherry., Method: A cross-sectional analytical study design was performed to collect data from 380 antenatal mothers. A convenient sampling technique was used to select the study participants. A structured, validated, self-administered questionnaire was used to collect data from pregnant women attending the antenatal outpatient department of Jawaharlal Institute of Postgraduate Medical Education and Research (JIPMER). Data were coded and analysed by IBM SPSS Statistics for Windows, Version 19.0 (Released 2010; IBM Corp., Armonk, New York, United States)., Results: This study revealed that almost half of the antenatal mothers (n=195, 51.3%) had adequate knowledge whereas 185 (48.7%) had inadequate knowledge regarding physical activity during pregnancy. Regarding their attitude, most of the antenatal mothers (n=303, 79.7%) had a favourable attitude and 77 (20.3%) had an unfavourable attitude towards physical activity during pregnancy. It was found that there is a significant association between education, employment, pre-pregnancy physical activity status, co-morbidities, and BMI of the antenatal mothers and their level of knowledge (p < 0.05). Also, educational status, employment status, level of activity in day-to-day life, pre-pregnancy physical activity status, co-morbidities, and number of antenatal visits attended by the antenatal mothers were significantly associated with their level of attitude (p < 0.05)., Conclusion: The level of knowledge regarding physical activity during pregnancy was adequate among antenatal mothers and their attitude seems to be favorable. This does not mean that they are exercising effectively. Therefore, health professionals should put forth their effort to bring about behavioural change among pregnant women towards exercise by conducting counselling sessions, and antenatal exercise classes during their antenatal care visits in order to empower pregnant women to lead a healthy pregnancy., Competing Interests: Human subjects: Consent for treatment and open access publication was obtained or waived by all participants in this study. Institutional Ethics Committee and Nursing Research Monitoring Committee of Jawaharlal Institute of Postgraduate Medical Education and Research, Puducherry issued approval JIP/CON/IEC/M.Sc./2022/OBG/2 and JIP/CON/NRMC/M.Sc./2022/OBG/2, respectively. Animal subjects: All authors have confirmed that this study did not involve animal subjects or tissue. Conflicts of interest: In compliance with the ICMJE uniform disclosure form, all authors declare the following: Payment/services info: All authors have declared that no financial support was received from any organization for the submitted work. Financial relationships: All authors have declared that they have no financial relationships at present or within the previous three years with any organizations that might have an interest in the submitted work. Other relationships: All authors have declared that there are no other relationships or activities that could appear to have influenced the submitted work., (Copyright © 2024, J et al.)