Background: One sub-population potentially affected by the COVID-19 pandemic are strength athletes who use anabolic-androgenic steroids (AAS). We examined links between disruption in AAS use and training due to the pandemic and mental health outcomes in this population, hypothesising: (a) the pandemic would be linked with reduced training and AAS use; and (b) athletes perceiving greater impact on their training and AAS use would report increases in detrimental mental health outcomes.Methods: Male strength athletes using AAS (N = 237) from 42 countries completed an online questionnaire in May 2020. A sub-sample (N = 90) from 20 countries participated again 4 months later. The questionnaire assessed pre-pandemic and current AAS use and training, alongside several mental health outcomes.Results: At Time 1, most participants perceived an impact of the pandemic on AAS use (91.1%) and/or training (57.8%). Dependent t-tests demonstrated significant reductions in training frequency (t = 7.78; p < 0.001) and AAS dose (t = 6.44; p < 0.001) compared to pre-pandemic. Linear regression showed the impact of the pandemic on training was a significant positive predictor of excessive body checking (B = 0.35) and mood swings (B = 0.26), and AAS dose was a significant positive predictor of anxiety (B = 0.67), insomnia (B = 0.52), mood swings (B = 0.37). At Time 2, fewer participants perceived an impact of the pandemic on AAS use (29.9%) and/or training (66.7%) than at Time 1. Training frequency (t = 3.02; p < 0.01) and AAS dose (t = 2.11; p < 0.05) were depressed in comparison to pre-pandemic. However, AAS dose had increased compared to Time 1 (t = 2.11; p < 0.05). Linear regression showed the impact of the pandemic on training/AAS use did not significantly predict any mental-health outcomes. However, AAS dose was a significant negative predictor of depressive thoughts (B = −0.83) and mood swings (B = −2.65).Conclusion: Our findings showed impact of the pandemic on the training and AAS use, reflected in reduced training frequency and AAS dose. However, whilst we detected some short-term consequential effects on mental health, these did not appear to be long-lasting.