In Indonesia a lot of bio-energy developed as an alternative energy source substitute for fossil fuels, one of them is biodiesel. The jarak kepyar oil is including nabati oil that prospective to be developed as bio-diesel material because it is a non-food ingredient. However, jarak kepyar oil has several weaknesses, among others, low heat value, density, and viscosity is still high. To improve the quality of biodiesel, there are several things that need to be done is by mixing biodiesel, which has better fiscal-chemical properties one of them with nyamplung oil biodiesel. Therefore, this study aims to determine the characteristics of density, viscosity, flash point and calorific value of biodiesel mixtures of castor oil (Ricinus communis) and nyamplung oil biodiesel (Calophyllum inophyllum) straw compared with biodiesel standard of SNI 7182-2015. This study consists of degumming, esterification and transesterification. The degumming method using phosphoric acid (H3PO4) with a ratio of 0.2% of the volume of oil, esterification method using 22.5% methanol of oil volume and the catalyst used Sulfuric acid (H2SO4) with a ratio of 0.5% of the volume of oil, transesterification using 15% methanol from volume of oil using a catalyst of Potassium Hydroxide (KOH) at a ratio of 1% of the volume of oil. The mixing of biodiesel was done at 80oC for 30 minutes using biodiesel ratio of kepyar distance with nyamplung biodiesel that is 100: 0, 20:80, 40:60, 50:50, 60:40, 80:20, 0:100 (%). Based on the comparative research results obtained on the mixture biodiesel distance keeper with nyamplung biodiesel on the composition of 20:80 (%) can improve the quality of biodiesel produced density 890,127 kg/m3, flash point 178oC, and calorific value 9097,7832 Cal/g, but the resulting viscosity value does not meet the SNI 7182-2015 biodiesel standard of 22.1 cSt.