A continuous microfluidic nanoprecipitation process has been investigated to prepare nanosized particles of a poorly water-soluble drug telmisartan (TEL), thereby enhancing its solubility and bioavailability. The present work aims to overcome agglomeration of drug particles by controlling the surface forces between the particles using various polymers like Polyvinylpyrrolidone K-30 (PVP K-30), Polyvinylpyrrolidone K-90 (PVP K-90), Poloxamer 188, Poloxamer 407, and hydroxypropyl methylcellulose (HPMC). The effect of process parameters such as solvent-to-antisolvent ratio, polymer-to-drug ratio, microchannel length, and solvent flow rate on drug particle size and polydispersity index (PDI) has been studied. The drug–polymer interaction investigated through X-ray diffraction (XRD) and Fourier transform infrared (FTIR) analysis revealed a significant reduction in peak intensity for Poloxamer 407 with no drug–polymer interaction. Also, the surface morphology of recrystallised TEL nanoparticles examined using field emission scanning electron microscopy (FESEM) showed clear and nearly uniform shaped particles. Poloxamer 407-based formulation of TEL exhibited minimum drug agglomeration with least particle size 369 nm and PDI value 0.049. The minimum particle size was achieved at solvent-to-antisolvent ratio 1:2, 1:1 polymer-to-drug ratio, microchannel length of 60 cm, and solvent flow rate of 30 mL/h. Thus, the microfluidic technique resulted in the production of TEL nanoparticles with narrow size distribution and useful morphological characteristics.