Description
On a quartered yellow and green rectangle arched convexly at top and bottom with a 1/8 inch (.32 cm) black border, a diagonal sword, white with black handle, from upper left to lower right point to base; between in second quarter, a yellow stylized hornet with white wings; and in third quarter, the white dome of the California State Capitol Building.  Attached above the rectangle, a yellow arched scroll edged with a 1/8 inch (. 32 cm) black border and inscribed “CSUS” in black letters.  Attached below the rectangle, a yellow arched scroll edged with a 1/8 inch (. 32 cm) black  border and inscribed “HORNETS” in black letters. 
Symbolism
The green and yellow quartered shield reflects the four semesters of the ROTC advanced course and alludes to the leadership excellence patch.  The sword represents the military leadership training of the Cadets.  The hornet denotes the school’s mascot.  The capitol dome recalls the school’s location and symbolizes the state university system and the academic standards of the university.  
Background

The shoulder loop insignia was approved on 29 July 1991. (TIOH Drawing Number A-10S-74)
http://www.tioh.hqda.pentagon.mil/Heraldry/SROTC/SROTC_School.aspx?s=8372