Different sized/shaped micro protrusive lens arrays atop poly(methyl methacrylate) can be fabricated by a simple two-step method, i.e., indentation followed by immersion in ethanol. Profile and projection of obtained microlenses were characterized. Thermal stability of microlenses was examined at 25°C and 60°C. This work demonstrates a cost effective approach for massive fabrication of microlens array with high reliability.