Background/Objective Few Spanish mindfulness interventions have been evaluated in Latinx patients with cancer. We culturally adapted a mindfulness intervention for Spanish speaking Latinx patients. The objective was to measure feasibility and acceptability as primary outcomes, with changes in anxiety, depression, and sleep as secondary outcomes. Method Spanish-speaking Latinx patients with breast cancer (n = 31) were randomized, between April 2021 and May 2022 to either intervention or wait-list control groups. The mindfulness intervention consisted of 6-weekly 1.5-hour sessions remotely delivered by a novice facilitator. Cultural adaptations included language, metaphor, goal, concept, trauma informed, and acknowledgement of spirituality. Feasibility was benchmarked as 75% of participants attending their first session, 75% of participants completing 4 of 6 sessions, and scoring ≥ 4 on a 5-point Likert feasability scale measuring ability to implement changes after 6-weeks. Acceptability was measured as scoring ≥ 4 on a 5-point Likert scale measuring usefulness and relevance of the mindfulness intervention for each session. An intention-to-treat, linear mixed model with repeated measures analysis examined changes in anxiety, depression, and sleep at week 6 and 18 (3 months post intervention). Results All three feasibility benchmarks were met with 75% of first session attendance, 96% of participants completing 4 of 6 sessions, and 94% scoring ≥ 4, on the feasibility scale (Mean (SD) = 4.3 (0.6)). Acceptability scores for both usefulness and relevance questions were ≥ 4 across all 6 sessions. Anxiety was significantly reduced at 3 months (−3.6 (CI -6.9, −0.2), P = .04), but is of unclear clinical significance given the small change. Depression scores declined, but not significantly, and there were no changes in sleep. Conclusion This culturally adapted, remotely delivered mindfulness intervention using a novice facilitator was acceptable and feasible and demonstrated associated reductions in anxiety amongst Spanish speaking Latinx patients with breast cancer. Trial Registration ClinicalTrials.gov ID# NCT04834154.