We developed a discovery-validation mass-spectrometry based pipeline to identify a set of proteins that are regulated in serum of patients with cervical intraepithelial neoplasia (CIN) and squamous cell cervical cancer using isobaric Tags for Relative and Absolute Quantitation (iTRAQ®), label-free shotgun and targeted mass-spectrometric quantification. At the discovery stage we used a “pooling” strategy for the comparative analysis of immunodepleted serum from patients with early-(CES) and late-stage (CLS) cervical cancer versus healthy controls that revealed 15 up- and 26 down-regulated proteins. The analysis of non-depleted serum samples from patients with CIN, CES, CLS, and healthy controls showed significant changes in abundance of alpha-1-acid glycoprotein 1, alpha-1-antitrypsin, serotransferrin, haptoglobin, alpha-2-HS-glycoprotein and vitamin D-binding protein. To further validate our findings we developed a fast UPLC/MRM method for the simultaneous targeted quantification of these proteins in an independent set of serum from patients with cervical cancer or CIN and healthy controls as well as serum samples from patients with ovarian cancer. The panel of six proteins showed 72 % sensitivity and 82 % specificity for discrimination of patients with CIN from healthy controls, a stage of the disease where current protein-based biomarkers, e.g. squamous cell carcinoma antigen fail to show any discrimination.