Studies of changes in health following immigration are inconsistent, and few are based on longitudinal designs to test associations based on change. This study identified factors that predicted changes in self-reported health (SRH) among California residents of Korean descent. A sample of California residents of Korean descent were interviewed and followed-up 2 or 3 times by telephone during 2001-2009. The questionnaires dealt with SRH, lifestyle behaviors (smoking, physical activity, and fast food consumption), and socioeconomic measures. Statistical analysis included random-intercepts longitudinal regression models predicting change in SRH. A similar percentage of respondents reported improved and deteriorating SRH (30.3% and 29.1%, respectively). Smoking, consumption of fast foods, age, percentage of life spent in the United States, and being female were predictors of deteriorating SRH, whereas physical activity, education, and living with a partner were predictive of improvement in SRH. The effect of immigration on SRH is influenced by socioeconomic factors and lifestyle practices. Results support promotion of healthy lifestyle practices among immigrants.