Background: The transnosographic nature of negative symptoms (NS) makes them fruitful for detecting psychiatric symptoms. The main objective of this study was to determine whether NS can be useful in screening for ultra-high risk of psychosis (UHR) or depressive symptoms in the no-help-seeking student population. The most prevalent NS and their relationship with cannabis use were also researched. Methods: From an online survey sent to students, 2128 filled out the Self-evaluation of Negative Symptoms (SNS), Prodromal Questionnaire 16 (PQ-16), Beck Depression Inventory (BDI), and Cannabis Abuse Screening Test (CAST). Results: 367 students (17.2%, 95% CI [15.6–18.9]) were considered to have UHR (PQ-16 distress score ≥ 9) and/or depression (BDI ≥ 16). The receiver operation characteristic curve showed that a threshold of 13 for the SNS score discriminated this subgroup of students with a sensitivity and specificity of 79.8% and 70.6%, respectively. The motivational dimension was overrepresented and linked to cannabis use. Conclusions: The early detection of NS in the no-help-seeking student population is relevant for detecting depressive and prodromal symptoms. This will enable early intervention to limit the progression to chronic mental disorders. The predominance of NS linked to the amotivational dimension was observed and related to cannabis use.