沈光漢,早年(nian)(nian)(nian)曾入(ru)粵軍(jun)(jun)(jun)第(di)(di)(di)一師(shi)(shi)(shi)軍(jun)(jun)(jun)官補習訓練班受訓。民國(guo)十(shi)(shi)(shi)(shi)(shi)四年(nian)(nian)(nian)(1925)由蔡(cai)廷鍇推薦,任(ren)(ren)(ren)(ren)粵軍(jun)(jun)(jun)第(di)(di)(di)一師(shi)(shi)(shi)第(di)(di)(di)一旅(lv)第(di)(di)(di)二團(tuan)(團(tuan)長(chang)(chang)(chang)(chang)蔣光鼐)第(di)(di)(di)三營(ying)(ying)(營(ying)(ying)長(chang)(chang)(chang)(chang)黃質勝)上尉營(ying)(ying)副。民國(guo)十(shi)(shi)(shi)(shi)(shi)六(liu)(liu)年(nian)(nian)(nian)(1927)秋任(ren)(ren)(ren)(ren)第(di)(di)(di)十(shi)(shi)(shi)(shi)(shi)師(shi)(shi)(shi)二十(shi)(shi)(shi)(shi)(shi)八(ba)(ba)團(tuan)代理團(tuan)長(chang)(chang)(chang)(chang)。民國(guo)十(shi)(shi)(shi)(shi)(shi)八(ba)(ba)年(nian)(nian)(nian)(1929)年(nian)(nian)(nian)三月(yue),任(ren)(ren)(ren)(ren)廣東編遣(qian)區獨(du)立(li)第(di)(di)(di)二旅(lv)(旅(lv)長(chang)(chang)(chang)(chang)蔡(cai)廷鍇)上校副旅(lv)長(chang)(chang)(chang)(chang)兼第(di)(di)(di)一團(tuan)團(tuan)長(chang)(chang)(chang)(chang)(該團(tuan)系原第(di)(di)(di)十(shi)(shi)(shi)(shi)(shi)師(shi)(shi)(shi)二十(shi)(shi)(shi)(shi)(shi)八(ba)(ba)團(tuan)改編)。是(shi)年(nian)(nian)(nian)秋,任(ren)(ren)(ren)(ren)第(di)(di)(di)六(liu)(liu)十(shi)(shi)(shi)(shi)(shi)師(shi)(shi)(shi)(由獨(du)二旅(lv)擴建(jian)的)一一九(jiu)(jiu)旅(lv)少將旅(lv)長(chang)(chang)(chang)(chang)。民國(guo)十(shi)(shi)(shi)(shi)(shi)九(jiu)(jiu)年(nian)(nian)(nian)(1930)升十(shi)(shi)(shi)(shi)(shi)九(jiu)(jiu)路(lu)軍(jun)(jun)(jun)六(liu)(liu)十(shi)(shi)(shi)(shi)(shi)師(shi)(shi)(shi)副師(shi)(shi)(shi)長(chang)(chang)(chang)(chang)(師(shi)(shi)(shi)長(chang)(chang)(chang)(chang)蔡(cai)廷鍇)。民國(guo)二十(shi)(shi)(shi)(shi)(shi)年(nian)(nian)(nian)(1931)獲四等寶鼎勛章。是(shi)年(nian)(nian)(nian)六(liu)(liu)月(yue)升第(di)(di)(di)六(liu)(liu)十(shi)(shi)(shi)(shi)(shi)師(shi)(shi)(shi)中(zhong)將師(shi)(shi)(shi)長(chang)(chang)(chang)(chang)。民國(guo)二十(shi)(shi)(shi)(shi)(shi)一年(nian)(nian)(nian)(1932)十(shi)(shi)(shi)(shi)(shi)月(yue),因“一·二八(ba)(ba)”淞滬抗日(ri)有功,獲青天白日(ri)勛章。民國(guo)二十(shi)(shi)(shi)(shi)(shi)二年(nian)(nian)(nian)(1933)十(shi)(shi)(shi)(shi)(shi)一月(yue)“閩變”爆(bao)發,任(ren)(ren)(ren)(ren)福(fu)建(jian)人民革命軍(jun)(jun)(jun)第(di)(di)(di)一方面軍(jun)(jun)(jun)第(di)(di)(di)一軍(jun)(jun)(jun)軍(jun)(jun)(jun)長(chang)(chang)(chang)(chang)(總(zong)司令蔡(cai)廷鍇)。閩變失敗(bai)后(hou)回(hui)住香港(gang)(gang)。民國(guo)二十(shi)(shi)(shi)(shi)(shi)六(liu)(liu)年(nian)(nian)(nian)(1937)抗戰(zhan)軍(jun)(jun)(jun)興,出(chu)任(ren)(ren)(ren)(ren)軍(jun)(jun)(jun)事參議員中(zhong)將參議,很少在軍(jun)(jun)(jun)界活動。三十(shi)(shi)(shi)(shi)(shi)五年(nian)(nian)(nian)(1946)以后(hou)被選為第(di)(di)(di)一屆國(guo)民大會(hui)代表,也曾任(ren)(ren)(ren)(ren)私立(li)德(de)業小學校長(chang)(chang)(chang)(chang)。1972年(nian)(nian)(nian)11月(yue)29日(ri)病逝于香港(gang)(gang),終年(nian)(nian)(nian)八(ba)(ba)十(shi)(shi)(shi)(shi)(shi)五歲(sui)。
1930年,沈光漢將軍(jun)任十(shi)九路軍(jun)六(liu)十(shi)師(shi)副師(shi)長(師(shi)長蔡廷鍇(kai))。
1931年,沈(shen)光(guang)漢(han)率(lv)(lv)所(suo)部(bu)第六(liu)十(shi)(shi)師(shi)駐防(fang)蘇州、常州一(yi)帶。1931年1月28日(ri)(ri)(ri),日(ri)(ri)(ri)軍進(jin)攻(gong)(gong)上(shang)海,蔡廷鍇即令沈(shen)率(lv)(lv)部(bu)開(kai)赴上(shang)海抗戰。1月30日(ri)(ri)(ri),沈(shen)部(bu)到達(da)上(shang)海南翔、真茹(ru)等地(di)待命(ming)。2月1日(ri)(ri)(ri),接替駐在閘北、虹(hong)口及(ji)(ji)八(ba)字橋等處七十(shi)(shi)八(ba)師(shi)的(de)防(fang)務。原七十(shi)(shi)八(ba)師(shi)翁照(zhao)垣旅劃(hua)歸沈(shen)光(guang)漢(han)指(zhi)(zhi)揮,沈(shen)師(shi)遂成為(wei)抗戰主力。七十(shi)(shi)八(ba)、六(liu)十(shi)(shi)一(yi)師(shi)為(wei)總預備(bei)隊。2月3日(ri)(ri)(ri)始,日(ri)(ri)(ri)軍相繼向吳淞、閘北及(ji)(ji)江灣進(jin)犯(fan),沈(shen)光(guang)漢(han)率(lv)(lv)所(suo)部(bu)及(ji)(ji)配屬部(bu)隊與之浴血(xue)戰斗30多天(tian),雖敵軍數倍于(yu)己,但沈(shen)師(shi)陣地(di)始終屹(yi)立不(bu)動。尤(you)其八(ba)字橋陣地(di),地(di)處要沖,敵軍在飛機、大炮、坦克的(de)配合下,輪(lun)番攻(gong)(gong)擊,沈(shen)率(lv)(lv)部(bu)堅決(jue)抵抗,僅2月7日(ri)(ri)(ri)一(yi)天(tian),就殲日(ri)(ri)(ri)軍千余(yu)人(ren),擊燒日(ri)(ri)(ri)軍前敵指(zhi)(zhi)揮雨(yu)田大佐。