Background: Chronic lymphocytic leukaemia (CLL) is a neoplasm of B-cells characterized by variable prognosis. Exploring the proteome of CLL cells may provide insights into the disease. Therefore, eleven proteomics experiments were conducted on eleven primary CLL samples. Results: We reported a CLL proteome consisting of 919 proteins (false discovery rate (FDR) ≤ 1%) whose identification was based on the sequencing of two or more distinct peptides (FDR of peptide sequencing ≤ 1%). Mass spectrometry-based protein identification was validated for four different proteins using Western blotting and specific antibodies in different CLL samples. Small sizes of nucleolin (~57 kDa and ~68 kDa) showed a potential association with good prognosis CLL cells (n = 8, p