Buenavista is located at the south of southwestern portion of the province of Marinduque. Bounded from North by the Municipality of Gasan to the Northeast by the municipality of Boac, to the south by the municipality of Torrijos and finally on the southwest by the Tablas Strait.
Buenavista, like most part of the province is generally rugged and mountainous with few alluvial plains mainly along the coast. Hence, the Poblacion of Marinduque is located at definitely flat terrain. Settlement areas are mostly concentrated along 0-8 % slope. Slopes with a range of 3-8 % are those areas with flat to rolling terrain conditions. Areas with slope range of 7-18 % are those areas with rolling to high terrain characteristics. Areas with 30 % and above slopes are those, which are mountainous and are generally located northwest and southeast of the Poblacion.
Buenavista has eleven (11) soil types, vast track of which is clay loam. It comprises 57.69 % of the total land area. It is very suitable for agriculture. Clay loam is further categorized into three (3), namely: Timbo clay Loam, Danhigan Clay loam and La Castellana clay loam. Almost half of the total land area has this kind of soil.
Being a tropical country, Buenavista has also a mean annual lowland temperature of about 27 degrees Centigrade or 80 degrees Fareinheight. The Municipality can be classified belonging to a climate characterized in Type IV, where there are two relatively dry months from February to April. It is largely dry from December to May. The rest of the year had rainfall more or less evenly distributed, with the month of October having the highest number of rainfall. However, rains are moderately intermittent even during the dry season with a relative peak of 7.1 inches, highest on October with 11.1 inches and lowest in April at 1.83 inches. Annual rain-days average 133 days, with a low of four days in April and as high as 15 days in October. It is exposed to the northeast monsoons and damaged by typhoons that pass occasionally. The coldest months occur usually from January to February when freezing breeze blow and snow from the upper continent melts. However, the hottest months are summer months of April to July.