IntroductionAlthough many effective treatment options exist, depression is still undertreated indicating gaps in the healthcare system. The complementary provision of mental healthcare through technologies (eg, computer, smartphone) has the potential to fill treatment gaps and to overcome access barriers to mental healthcare. Until now, no systematic review integrates the evidence on different technology-based psychological interventions (TBIs) concerning their effectiveness and acceptance in different clinical phases of depression management (bridging waiting periods, acute treatment and aftercare). The aim of this project is to structure evidence on TBIs regarding different phases of depression management, and to determine effectiveness and acceptance for each clinical phase considering both active (eg, face-to-face treatment) and inactive (eg, waitlist) controls as comparators.Methods and analysisWe will include studies on adults with a formal diagnosis of unipolar depression. Treatments delivered by technologies based on scientific psychological theories will be considered as experimental interventions. The primary effectiveness outcome will be depressive symptoms at study endpoint measured by symptom severity rating scales, and the primary acceptance outcome will be dropping out of the study due to any reason. We will consider only randomised controlled trials, which will be identified by key database searches (including Cochrane Central Register of Controlled Trials, Medline, PsycINFO, PSYNDEX, CINAHL) complemented through searches in clinical trial registries (eg, clinicaltrials.gov) and grey literature searches (eg, Open Grey). Two review authors will independently conduct study selection, data extraction and quality assessment of included studies (using the Cochrane Collaborationâs tool for assessing risk of bias). Meta-analyses applying random-effect models as well as subgroup, meta-regression and sensitivity analyses will be performed.Ethics and disseminationEthics approval is not required for this study, as we conduct research on secondary data. We will disseminate results via peer-reviewed journal publications, presentations on conferences and via plain language summaries.PROSPERO registration numberCRD42016050413; Pre-results.