Background: Diabetes is the most common complication during pregnancy. Health consultation and lifestyle modification are considered as the basis for management of diabetes and confronting its risks. Therefore, the present study was conducted to compare the effect of group and phone consultations on the lifestyle of women with gestational diabetes.Methods: The present clinical trial was conducted on 66 pregnant women with gestational age of 24-28 week, who had gestational diabetes in Yazd in 2018. Participants were divided into three groups of 22; control group and phone consultation. Group consultation was conducted during eight 2-hour sessions and phone consultation was performed through eight 30-45-minute sessions, weekly. Data gathering tools included demographic characteristics and health improvement lifestyle questionnaires. Data were analyzed using descriptive statistics, parametric tests and SPSS software version 16. The level of significance was set at p < 0.05.Result: In the beginning of the study no significant difference was observed between the three groups regarding their demographic characteristics and the score of lifestyle (p > 0.05). The score of lifestyle was increased in both the groups of group and phone consultation immediately and one month after the intervention and the increase was statistically significant (p < 0.001). But the difference in the control group was not significant (p = 0.126).Conclusions: Considering the results of the study, it is better to use group consultation and if necessary, phone consultation, for educating and empowering risky pregnant mothers for preventing and controlling the complications of diseases.