Mesoporous crystalline phase of nickel phosphate (m-NP) have been synthesized by a simple low-temperature hydrothermal approach. For the first time, the antimicrobial activities of m-NP are studied using different microbial media. The chemical structure and crystallinity of the m-NP are studied by XRD pattern and is confirmed by FT-IR results. The morphology is verified by scanning electron microscopy (SEM) and transmission electron micrographs (TEM). According to BET studies, the total pore volume is found to have an average value of 0.074 cc/g with surface area of 29.0 m²/g. m-NP particles are screened for antimicrobial activities against one G-positive bacteria, three G-negative bacteria and C. albicans fungal pathogen. The results show that the m-NP exhibits good antimicrobial activities against both G-positive and G-negative bacteria and against C. albicans with good selectivity against G-negative bacteria.