Introduction: According to recent global estimates there are nearly 530 million cases and 6.3 million deaths due to novel coronavirus disease 2019 (COVID-19) pandemic. Studies have shown that COVID-19 disproportionately affects males than females. In this study we looked at differences in in-hospital outcomes of COVID-19 based on sex using a larger administrative database. Hypothesis: The adverse in-hospital outcomes of COVID-19 will be significantly higher among males. Methods: This was a retrospective analysis of the California State Inpatient Database 2020. All COVID-19 hospitalizations with age 18 years and above were included for the analysis. These hospitalizations were classified into males and females. The main outcomes of the study were in-hospital mortality, prolonged length of stay, vasopressor use, mechanical ventilation, and ICU admission. Any length of stay ≥75th percentile value for the entire cohort was considered as prolonged length of stay. Logistic regression analyses after adjusting for covariates were used to compare COVID-19 related outcomes between males and females. Results: A total of 95,180 primary COVID-19 hospitalizations were included for the analysis. Of these 52465 (55.1%) were males and 42715 (44.9%) were females. Among these hospitalizations, mortality (12.4% versus 10.1%, P<0.001), prolonged length of stay (30.6% versus 25.8%, P<0.001), vasopressor use (2.6% versus 1.6%, P<0.001), mechanical ventilation (11.8% versus 8.0%, P<0.001), and ICU admission (11.4% versus 7.8%, P<0.001) were significantly higher among males. Logistics regression analysis showed that males had significantly greater odds for mortality (aOR, 1.38, 95% CI: 1.32-1.44), prolonged length of stay (aOR, 1.35, 95% CI: 1.31-1.39), vasopressor use (aOR, 1.59, 95% CI: 1.51-1.66), mechanical ventilation (aOR, 1.62, 95% CI: 1.47-1.78), and ICU admission (aOR, 1.58, 95% CI: 1.51-1.66). Conclusions: Adverse outcomes such as mortality, prolonged length of stay, vasopressor use, mechanical ventilation, and ICU admission were independently associated with male sex. These findings could be due differences to both biological and social factors between the sexes. Future studies should explore these factors to efficiently control COVID-19.