The most common cause of suicidal tendencies is depression, which is mainly characterized by low mood, lack of interest and loss of pleasure, which is why they feel particularly miserable and pessimistic about the future, so they will have negative thoughts or even anorexic thoughts, and eventually they will not want to live, or even commit suicide. 2, the main cause of suicide may be schizophrenia, such as hallucinations, delusions and even many strange and bizarre behavior and ideas, there may be some psychotic symptoms under the influence of the problem of suicide, such as the emergence of verbal hallucinations, hearing someone in the air to order him to commit suicide to jump, this time is very dangerous. 3, the common cause of suicide may be anxiety and irritability, if the patient is particularly anxious, upset, fidgety, in this case of extreme anxiety is also prone to suicidal tendencies. 4, mostly seen in particularly intense, or conflict is particularly significant, such as arguments with others, by the leadership or criticism of their loved ones, as well as their own funds have a significant loss of time, this time a momentary inability to think, there may also be suicidal tendencies.