The meaning in life consists of an individual's values, experiences, goals and beliefs. It has been shown to be negatively associated with depression, hopelessness and suicidal ideation. Depression and hopelessness are related to increased suicidal ideation. Meaning in life has been shown to be a protective factor against depression, hopelessness and suicidal ideation. A path model was developed to clarify the associations among meaning in life, depression, hopelessness and suicidal ideation. For clarity, the outcomes were depression and suicidal ideation, the independent variable was hopelessness, and the mediator was meaning in life. Hopelessness had a direct association with meaning in life, and meaning in life had a direct association with depression, supporting the mediating effect of meaning in life from hopelessness to depression. Meaning in life had the strongest association with depression, and depression had the strongest association with suicidal ideation. Meaning in life did not have a significant direct association with suicidal ideation; it did have an indirect association with suicidal ideation through depression. This study estimated that one-point increase in meaning in life score was associated with 0.47-point decrease in depression score and 0.13-point decrease in suicidal ideation score, respectively. Logotherapy is a meaning-centred therapy to find meaning in life. This study reveals that increased levels of meaning in life are associated with decreasing degrees of depression. Mental health nurses could help patients to find meaning in life by logotherapy and thus associated with reductions in depression. Mental health nurses could help patients to find hope by exploring meaning in life and promoting positive attitudes towards life from meaningless life to meaningful life, there is a reduction in depression, which in turn reduces suicidal ideation indirectly. Introduction Meaning in life can be good protective factor against depression, hopelessness and suicidal ideation. Aim To analyse the mediating effect of meaning in life on the associations among hopelessness, depression and suicidal ideation. Method A cross-sectional study was conducted among 90 patients diagnosed with depression. A structural equation modelling approach was applied for this path analysis to examine the mediating effect of meaning in life on the association among hopelessness, depression and suicidal ideation. Results The results showed that meaning in life mediated the association between hopelessness and depression. Hopelessness had a direct positive association with depression (β=0.23, p<.03), and meaning in life had a direct negative association with depression (β=-0.51, p<.01) and indirect association with suicidal ideation through depression; this indirect association was -0.21 (p<.01). Discussion Meaning in life revealed strong mediating association with the relationship between hopelessness and depression. By reducing the level of depression, meaning in life demonstrated its mediator association with suicidal ideation. Implications for Practice Logotherapy is a meaning-centred therapy to find meaning in life. Mental health nurses could help patients to manage their depression through logotherapy, thus leading to reductions in suicidal ideation.