Efficient separation and purification of proteins like C-phycocyanin (C-PC) from Spirulina platensis are essential for their commercialization, yet remain challenging. This study investigates three chromatographic methods: weak anion exchange chromatography (DEAE), strong anion exchange chromatography (Q Sepharose), and hydrophobic interaction chromatography (HIC) for C-PC purification. DEAE chromatography achieved a recovery of 36.80 mg unit (57.08%) with a purity of 3.23, outperforming Q Sepharose (yield: 23.21 mg unit means that 46.33%, purity: 2.76) and HIC (yield: 22.95 mg unit means that 17.57%, purity: 3.02). The purified C-PC consisted of α and β subunits with molecular masses of 16 kDa and 17 kDa, respectively. Further assessment revealed its antioxidant capacity through an ABTS assay. C-PC stability was tested at different pH levels and temperatures. Maximum stability was observed at pH 7, while pH 4 showed the lowest stability. Glutaraldehyde-treated C-PC (GC-PC) demonstrated gradual degradation up to 50°C, retaining 73.25% after 30 min. Notably, GC-PC exhibited stability even at higher temperatures, with degradation rates of 57.32% at 70°C and 50.96% at 80°C. DEAE chromatography proved superior for C-PC purification, offering higher yields and purity compared to Q Sepharose and HIC. The purified C-PC showed promising antioxidant capacity and stability, particularly GC-PC, which exhibited resistance to degradation even at elevated temperatures. These findings underscore the potential of C-PC as a valuable compound for various applications, with DEAE chromatography being an efficient method for its production and commercialization. This article is protected by copyright. All rights reserved.