In the modern scenario, there has been an increasing demand for an efficient miniaturized heat transfer device capable of removing high heat flux. Miniature loop heat pipes (MLHPs) are quite promising and are expected to play a major role in the thermal management of modern technologies. MLHPs are passive two-phase heat transfer devices, which work on the capillary mechanism for the pumping of the working fluid. However, they are complex systems where the thermal and hydrodynamic mechanisms between the different components are strongly coupled. In this work, a one-dimensional steady-state mathematical model of MLHP is developed to calculate the saturation temperature of evaporator for a given heat load and sink temperature. The model incorporates separated flow model for the calculation of two-phase pressure drop including both frictional and acceleration pressure drop in the condensing tube for computing the two-phase flow within the miniature loop heat pipe. It can predict the operating temperature, thermal resistance, heat leak and the varying two-phase length. The model is validated with the experimental data available in the literature and a decent agreement is obtained among the model predictions and experimental data. Parametric studies are conducted to investigate the effect of varying heat load, sink temperature, orientation and geometrical configuration such as transport line diameter and length on the operating evaporator temperature.