Mental disorders and sleep dysfunction are common among Chinese university students. This study aimed to evaluate a low cost scalable mindfulness intervention program to improve psychological health and sleep quality among Chinese university students. A randomized controlled trial with 101 university students (mean age 22.30 ± 2.63, 69.31% female) was conducted. Participants were randomized into 4 groups: Group 1: control group (n = 25), Group 2: mindfulness only group (n = 27), Group 3: mindfulness + plain-text reminder group (n = 24), and Group 4: mindfulness + enhanced text reminder with animal meme group (n = 25).The mindfulness intervention consisted of two in-person guided sessions along with weekly self-guided practice for 7 weeks. The Depression, Anxiety and Stress Scale (DASS-21) and The Pittsburgh Sleep Quality Index (PSQI) were used to measure depression, anxiety, stress, and sleep dysfunction. After the intervention at week 4, compared to controls, completers in group 2, 3 and 4 (n = 42) showed significantly reduced depression (Cohen's d = 0.83), anxiety (Cohen's d = 0.84), and stress (Cohen's d = 0.75), and improved subjective sleep quality (Cohen's d = 2.00), sleep latency (Cohen's d = 0.55), and habitual sleep efficiency (Cohen's d = 0.86). The effect was maintained at week 7. Low-intensity mindfulness interventions might be a useful intervention program in university settings.