Unaspis mabilis Lit & Barbecho (Hemiptera: Diaspididae) adversely affects lanzones production in the Philippines. Characterized as having an aggressive behavior, this leaf-inhabiting species spreads fast and is difficult to control. Since its identification in 2014, it has already reached different parts of the country causing significant damage. Spatial distribution of U. mabilis in lanzones and the effects of weather on its population density were investigated for six months from November 2018 to April 2019 in two orchards in Jumarap, Banga, and Calizo, Balete in Aklan, Philippines. Spatial distribution was measured using dispersion parameters and dispersion indices, whereas correlation study was conducted employing simple and multiple regressions for species’ adult female population counts obtained every 15 days from 30 randomly selected trees. Dispersion parameters and indices confirmed the aggregated distribution of U. mabilis. This aggregated nature was witnessed when pest was highly active from February to April 2019, and during periods of low activity from November 2018 to January 2019. This observed spatial pattern can be linked to the species’ social behavior, the overall effect of their major mortality factors, and the morphological traits of the lanzones plant. Weather parameters such as minimum and maximum temperatures had positive main effects, while high relative humidity and maximum wind speed had negative main effects on species’ population. However, the interaction between maximum and minimum temperatures showed a negative impact, whereas the combination of high relative humidity and maximum wind speed exhibited a positive influence. Rainfall displayed no effect on species’ population change. Resulting data on the spatial distribution and the effects of weather on population can be used as bases for the proper estimation of infestation for an effective pest management against the frequent attack of U. mabilis in lanzones.