(Problem) To provide boron nitride particles which have a scale shape with a small diameter/thickness ratio (aspect ratio) and which have a high purity and high crystallinity at the sub-micron level. (Solution) These boron nitride particles are characterized by having an average particle diameter of 0.05-2.0 (mu)m, a graphitization index of 3 or lower, a total oxygen content of 0.20 mass% or lower, and a lower average value for the long-axis diameter/thickness ratio of the scale-shape particles of 6.0 or lower. This method of producing boron nitride particles is characterized by introducing, into a reactor vessel, ammonia and boriate alkoxide at an ammonia/borate alkoxide molar ratio of 1-5 in an inert gas atmosphere, heating for 30 seconds or less at 800-1,350DEG C, and after obtaining boron nitride precursors, heating said boron nitride precursors in an inert gas atmosphere at 1,650-2,200DEG C for 0.5 hours or longer.