The pH-dependent complexation behaviors of natural and counterionic polyelectrolyte complexes (PECs) without crosslinkers have been rarely studied. In this work, alginate (0.5-2.5 wt %) and chitosan (0.5-2 wt %) were combined to formulate turbid gel-like assemblies. The PEC was consisted of~100-μm-sized porous structure observed by scanning electron microscope images and electrostatic interactions inside the complex were newly formed characterized by Fourier transform infrared spectra. Based on visual monitoring and ultraviolet-visible absorption measurement, the complex maintained the gel-like structure under acidic, while the complex was more dissolved under becoming basic. As a demonstration of potential pH-dependent delivery, distinct release profiles of the complexes encapsulating rhodamine 6G (R6G) or doxorubicin, were observed when they were immersed in acidic, neutral, and basic medium. Within 2 h, 7.4, 35.4, and 73.7% of R6G were released under acidic, neutral, and basic condition, respectively, with reasons of degree of protonation or deprotonation of each natural polyelectrolyte at certain pH.