Rapeseed meal, a byproduct of oil extraction, is increasingly recognised as a valuable source of plant protein and health-promoting peptides. This study aimed to identify key proteins in cold-pressed rapeseed meal and assess their potential to release bioactive peptides through in silico hydrolysis using plant-derived proteases, namely papain, bromelain, and ficin. Proteomic profiling via two-dimensional electrophoresis and MALDI-TOF/TOF mass spectrometry revealed cruciferin as the dominant protein, along with other metabolic and defence-related proteins. In silico digestion of these sequences using the BIOPEP database generated thousands of peptide fragments, of which over 50% were predicted to exhibit bioactivities, including ACE and DPP-IV inhibition, as well as antioxidant, neuroprotective, and anticancer effects. Among the evaluated enzymes, bromelain exhibited the highest efficacy, yielding the greatest quantity and diversity of bioactive peptides. Notably, peptides with antihypertensive and antidiabetic properties were consistently identified across all of the protein and enzyme variants. Although certain rare functions, such as anticancer and antibacterial activities, were observed only in specific hydrolysates, their presence underscores the broader functional potential of peptides derived from rapeseed. These findings highlight the potential of rapeseed meal as a sustainable source of functional ingredients while emphasising the necessity for experimental validation to confirm the predicted bioactivities.