Individuals with psoriatic nails often have a lower quality of life relative to their counterparts with healthy nails. Methotrexate (MTX), an anti-neoplastic agent, is a longstanding treatment option for nail psoriasis. In the current study, we compared the effects of MTX to that of a corticosteroid, namely, methylprednisolone acetate (i.e., Depo-Medrol®) across individuals with nail psoriasis. We used a cohort study design, and both agents were administered intralesionally. Outcome variables were based on the Nail Psoriasis Severity Index (NAPSI). We quantified the effect in terms of change in NAPSI, complete cure at week 16, and cure between 32 and 36 weeks. Our regressions demonstrated that reduced NAPSI scores with Depo-Medrol were, on average, greater than that with MTX by 2.27 (n = 48, P = 0.000255) at week 16. Similarly, the odds of complete cure at week 16 was greater with Depo-Medrol® than with MTX (odds ratio = 18.6, P < 0.0001). In terms of both complete cure and change in NAPSI, Depo-Medrol® was significantly more effective than MTX at a follow-up period of 32-36 weeks. Our study established that intralesional Depo-Medrol® is more effective than intralesional methotrexate for treating nail psoriasis.