The interactions of succinylated collagen (SC) and carboxymethyl cellulose (CMC) in neutral solutions (pH ∼ 6.9) were investigated, which could provide information for the fields of tissue engineering and cosmetics. According to the results from viscometric measurements, the SC and CMC molecules were possibly compatible as CMC ≤ 50%. Ultrasensitive microcalorimetry reflected the increase in the values of transition temperature (Tm) and heat capacity change (ΔCp) as CMC ≤ 50%, while both of them decreased as the CMC content further increased. Two-dimensional Fourier transform infrared spectroscopy analysis confirmed the hydrogen bonding and electrostatic interactions between SC and CMC, and the hydrogen bonding interaction played a key role as CMC ≤ 50%, while electrostatic interaction became predominant as more CMC was added. Atomic force morphology revealed the changes in the aggregation of SC induced by the addition of CMC.