This study was conducted to evaluate whether smart cell phones detach people from social life, make them lonely, cause depressive symptoms and whether there is a relationship between them. This is a cross-sectional study using face-to-face survey method. The sample was determined as 376 participants, with 95% confidence interval, 50% probability depending on the probability of having a smartphone or not. Participants in the sample were determined by systematic random sampling from adults aged 20 and over in Çiftlik district of Niğde province. The NMP-Q, DASS-42 and UCLA-LS were used. The median age of the 376 participants (192 male, 184 female) was 30 and the mean age was 32.0 (±10.94) years. Participants that had social media accounts were 68.9% of the population. Over 70% of the participants had mild, moderate or severe nomophobia. Nomophobia status of the participants was affected by the mean duration of the first-time smartphone use (P = .017), the mean daily smartphone usage time of the participants (P < .001), the mean number of smartphone users in the participants’ families (P = .003), the mean depression and stress scores of the participants (P < .001), having social media account (P = .001), and declaration of smart phone dependency (P = .005). Nomophobia status was not affected by participants’ gender, mean age, educational level, employment status, economic status and marital status (P > .05). The duration of daily smartphone use, the duration of first-time smartphone use, and having multiple smartphone users in family increased nomophobia. Also, having active social media accounts and self-reported smartphone addiction found correlated to nomophobia. Smartphone addiction increases depression, anxiety, and stress scores of the participants.