Here is a list of faculties who work on complex systems in Iran, sorted by the cities:
Tehran

Statistical Physics, CFT, Self-Organized Critically, Econophysics and Neuroscience

Critical Phenomena, Conformal Field Theory, Evolutionary Theory

Phospholipid Membranes, CFT and Logarithmic CFT, Disordered Systems, Rough Surfaces, Stochastic Processes, ...

Statistical Physics, Conformal Invariance, Percolation Theory, Growth Models, Tumor Growth

EconoPhysics, Complex Networks, Sociophysics, Network science

Complex systems, Cosmology

Econophysics, Complexity Economics, CFT

Quantum Statistical Mechanics, Solar Physics, Magnetized stars

Complex Networks, Interconnection Networks, Storage Systems

Econophysics, Finance

Computational Condensed Matter Physics, Nanoscale Heat Transport, Wave Propagation

Dynamical Systems and Chaos, Statistical Mechanics of Disordered Systems, Stochastic processes, Anderson Localization, Quantum Transport
Isfahan

Structure and Dynamics of Complex Networks

Theoretical Condensed matter, Statistical Physics

Neuroscience and Biophysics, Quantum Technologies, Data Science, Machine Learning (Quantum and Classical)
Zanjan

Complex Networks, Percolation Theory, Critical Phenomena

Theoretical neuroscience, Dynamical systems

Neuroscience, Sandpile Model, The Intermittency issue in Burgulence and Turbulence, Surface growth model

surface growth, complex systems and economy

Structure and Dynamics of Complex Networks, System Biology

Statistical physics, soft matter, traffic flow, solar energy

Computational Physics, Biophysics, Geophysics, Mathematical Economics, Nonlinear Systems, Nonlinear Dynamics

Phase Transitions, Condensed Matter, Superconductivity, Low Temperature Physics
Shiraz

Statistical Physics, Phase Transitions, Neuroscience, Relativistic Thermodynamics

Statistical Physics, Disordered Systems, Optimization Problems
Bushehr

Statistical Mechanics, Stochastic Processes, Complex Networks
Ardabil

Self-organized criticality