AimsThe predictive value of the lactate/albumin ratio (LAR) in mortality is established in various conditions, yet its relevance to 3‐month readmission risk in Chinese adults with heart failure (HF) remains unclear.Method and resultsAnalysing data from 957 patients with HF at Zigong Fourth People's Hospital, Sichuan, China (December 2016 to June 2019), we assessed baseline characteristics, vital signs, comorbidities, and prescriptions. LAR demonstrated a linear correlation with 3‐month readmission risk (HR = 1.60, 95% CI: 1.19–2.16). Tertile 3 (≥−0.48) exhibited higher risk than tertile 1 (<−0.83) and tertile 2 [−0.83, −0.48), with HRs and 95% CI of 1.49 (1.06–2.10), 1.43 (1.01–2.02), 1.48 (1.03–2.12), respectively. Subgroup and sensitivity analyses affirmed consistent influence of LAR on 3‐month readmission risk for HF.ConclusionsHigher LAR significantly correlates with increased 3‐month readmission risk in Chinese adult patients with HF, suggesting LAR is a valuable predictor for early readmission.