Covalent organic frameworks (COFs) are new functional porous materials that can be arranged in layered 2D or 3D periodic networks. COFs demonstrate properties such as thermal stability, large surface area, large pore volume, and low mass density. It was discovered that these materials could have high thermoelectric efficiency due to the large Seebeck coefficient and low thermal conductivity and metal ion selection is the key to improve the thermoelectric properties [1, 2]. Controlling the physical dimensionality of materials has led to profound new scientific discoveries and entirely new possibilities for electronic and optoelectronic applications. Nanomaterials, which can be obtained as atomically thin 2D sheets have been attracting considerable attention, especially after the isolation of graphene, for addressing fundamental issues related to their strictly 2D electronic structure and for enabling their integration in nanotechnological devices. The 2D sheet assemblies are necessary when considering the use of such coordination materials, which frequently incorporate functional π-electron components, in nanotechnological thin film devices.  The DFT and the Boltzmann transport equation have been applied to calculate the semiclassical thermoelectric transport coefficients for both bulk and 2D sheets of metallophthalocyanine COFs MPc-COFs (M = Co, Cu, and Zn). In the crystal structure of studied MPc-COFs the layers prefer a slipped-AA stacking. This structural character in these compounds suggests that the charge carrier transport originates from the π-macrocycles‘ stacking direction. The insertion of an electron deficient building block benzothiadiazole in MPc-COFs has led to positive Seebeck coefficients along cell directions. The relaxation time was estimated from DFT band structure calculations and experimentally defined mobility to determine the electronic and thermal electronic conductivities and ZT estimation. The low-dimensional transport of holes in valence band and conduction band has led to the large Seebeck coefficients.