The porphyritic texture of diamond films synthesized by hot filament CVD (HFCVD) is reported for the first time. The porphyritic texture has two distinct crystal habits, where phenocrysts are set in a matrix of fine grains. The morphology and quality of films were investigated by scanning electron microscopy and Raman spectroscopy. A growth model employing secondary nucleation and growth illuminates the growth mechanism of this unusual texture. We also compare the similarity and difference between Wild's and our results on the spherical shape of a multiple faceted particle, which is formed by multiple