Background and Aims: There are limited reports analyzing opioid overdose (OD) mortality data during the COVID-19 pandemic. There is also great heterogeneity in outcomes across states, necessitating assessments of the effects of COVID-19 on OD deaths on a state-by-state level. This report aims to analyze overall trends in OD deaths in Massachusetts during COVID-19. Design: Using individual-level death records in Massachusetts, we identified and analyzed OD mortality trends during the COVID-19 pandemic as compared to 2018 and 2019. We analyzed the period between March 24 (stay-at-home order in 2020) and August 11 (latest reliable data). We also estimated the correlation between OD deaths and COVID-19 case fatality rates at the county level. Setting: Massachusetts. Participants: A total of 2,342 OD deaths were analyzed. Measurements: The outcomes studied were OD deaths and COVID-19 case fatality rates. Findings: OD deaths involving cocaine and amphetamines increased from 2019 to 2020, by 20% (276 vs. 330; P<0.01) and 79% (33 vs. 59; P<0.01), respectively, but were steady from 2018 to 2019. Heroin's presence continued to decrease (238 in 2018, 161 in 2019, 102 in 2020; P<0.001); however, fentanyl was present in more than 90% of OD deaths, reflecting its continued domination of the illicit opioid supply in Massachusetts. Prescription opioid presence was stable. 79% of OD decedents were White and 6% were Black in 2019, as compared to 74% and 10% in 2020 (P=0.01). We found no significant correlation between COVID-19 case fatality and OD death rates. Conclusions: Increased deaths involving stimulants and alcohol reflect concerning trends in the era of COVID-19. Rising OD death rates among Black residents underscore that interventions focused on racial equity are necessary. Surveillance efforts must utilize up-to-date data to measure COVID-19 impacts on OD death and respond to imminent threats in real time.