Based　on　Mg/Na　(NO3)(2)　and　Mg/Sr　(NO3)(2),　the　combustion　and　radiation　characteristics　of　pyrotechnics　in　vacuum　were　studied.　The　burning　rate　and　visible　light　radiation　characteristics　of　different　samples　were　obtained,　and　the　relationship　between　combustion　performance　(visible　light　intensity　and　burning　rate)　of　the　sample　and　vacuum　environment　pressure　were　further　obtained.　The　results　show　that:　1)　the　linear　burning　rate　and　mass　burning　rate　of　the　two　formulations　decrease　with　the　decrease　of　pressure,　and　the　burning　rate　has　an　exponential　relationship　with　the　pressure,　and　the　sensitivity　of　Mg/Sr　(NO3)(2)　to　ambient　pressure　is　slightly　higher　than　that　of　Mg/Na　(NO3)(2);　2)　Under　the　same　vacuum　pressure,　the　visible　radiation　intensity　of　Mg/Sr　(NO3)(2)　is　significantly　higher　than　that　of　Mg/Na　(NO3)(2);　3)　With　the　decrease　of　vacuum　pressure,　the　visible　light　radiation　intensity　of　the　two　formulations　of　pyrotechnic　composition　decreased.　4)　According　to　the　test　data,　the　light　intensity　pressure　index　of　Mg　/　Na　(NO3)(2)　is　1.07,　which　is　more　sensitive　to　environmental　pressure　than　that　of　Mg/Sr　(NO3)(2)　system　0.598;　5)　Based　on　the　fitting　formula,　it　is　estimated　that　the　visible　light　radiation　intensity　of　Mg/Na　(NO3)(2)　system　is　16cd,　which　is　much　less　than　that　of　Mg/Sr　(NO3)(2)　system　443cd.