Introduction: There has been a secular trend in the age of menarche of females at the rate of decrease of 1 month per decade since 1995. Hormonal imbalance, obesity, altered food habits, chemicals in cosmetics, and sedentary life have been the main causes. Mobile phone addiction in small children should also be considered for any association. Aim: The aim is to find out the trend of age of onset of menarche and its association with mobile phone usage in females of rural and urban areas in the past 5 years, since 2014. Materials and methods: The study was conducted among 378 females (196 rural and 182 urban) of age group 7-15 years in the rural and urban population. After obtaining written consent, a questionnaire was administered to know their current age, age of menarche and details about their mobile phone exposure. Results and discussion: The average age of menarche in urban and rural females was 11.95 ± 0.73 years and 12.47 ± 0.54 years respectively. 120 urban girls and 105 rural girls use cell phone, mainly for games (rural) and for calls in urban side, of which less than 1/3rd were only using hands-free devices. None of the urban or rural girls using cell phone were aware of the hazards of it. Conclusion: Direct exposure of radiation to brain may alter Hypothalamo-pituitary axis, which might affect Gonadotrophin secretion, leading to early menarche. Though this might be a theoretical correlation, mobile phone exposure should be considered for association with early menarche, as this has serious consequences on the physical, psychological and social health of the female.