Background The COVID-19 pandemic psychologically affected children and their caregivers. On the other side, parents were adapting to new daily routines for work, education, and self-care in response to the current situation. Therefore, assessing the child-parent relationship during the quarantine period is a crucial issue. Objective This study aimed to measure the impact of quarantine during the COVID-19 period on the relationship between children and their parents in the western region of Saudi Arabia, mainly in Jeddah and other nearby cities. Methods A cross-sectional survey study was conducted from April to December 2020 in the western region of Saudi Arabia, primarily Jeddah and neighboring cities, during the COVID-19 quarantine and shortly after it was stopped. A validated survey (Child-Parent Relationship Scale (CPRS)) comprising socio-demographic characteristics, conflict, and closeness of the child-parent relationship was distributed to the respondents after being translated from English to Arabic. Statistical analysis was conducted using the Statistical Package for the Social Sciences (IBM SPSS Statistics for Windows, IBM Corp., Version 26.0, Armonk, NY). P-values less than 0.05 were considered statistically significant. Results The study included 361 parents with a mean (SD) age of 37.30 (7.77) years old. Most parents were mothers (77.9%, N=279), married (91.3%, N=326), lived with their children (98.3%, N=354), and had three or a lesser number of children (80%, N=287). The average time spent with children was significantly higher after the quarantine (12.96 hours) compared to before the quarantine (8 hours) (p<0.001). The number of hours spent with children before the quarantine was significantly higher for mothers than fathers (8.44 vs. 6.01 hours, respectively, p<0.001). There was a significant association between the mean difference in conflict scores before and after the quarantine and the age of parents (p=0.002), the gender of parents (p<0.001), and marital status (p=0.026). There was a significant correlation between mean differences in closeness scores before and after the quarantine and the gender of parents (p=0.038). Conclusion Our findings highlight the complex and varied effects of the pandemic on parent-child relationships. The results emphasize the need for support and interventions to address increased conflict and promote positive relationships between parents and children during challenging times.