As　one　of　the　primary　elements　in　magnetoresistive　random　access　memory　(MRAM),　voltage　controlled　magnetic　anisotropy　magnetic　tunnel　junction　(VCMA-MTJ)　has　received　wide　attention　due　to　its　fast　read　and　write　speed,　low　power　dissipation,　and　compatibility　with　standard　CMOS　technology.　However,　with　the　downscaling　of　VCMA-MTJ　and　the　increasing　of　storage　density　of　MRAM,　the　effect　of　process　deviation　on　the　characteristics　of　MTJ　becomes　more　and　more　obvious,　which　even　leads　to　Read/Write　(R/W)　error　in　VCMA-MTJ　circuits.　Taking　into　account　the　depth　deviation　of　the　free　layer　(gamma(tf))　and　the　depth　deviation　of　the　oxide　barrier　layer　(gamma(tox))　in　magnetron　sputtering　technique　as　well　as　the　etching　process　stability　factor　(alpha)　caused　by　the　sidewall　re-deposition　layer　in　the　ion　beam　etching　process,　the　electrical　model　of　VCMA-MTJ　with　process　deviation　is　presented　in　the　paper.　It　is　shown　that　the　VCMA-MTJ　cannot　achieve　the　effective　reversal　of　the　magnetization　direction　when　gamma(tf)　＞=　13%　and　gamma(tox)　＞=　11%.　The　precession　of　magnetization　direction　in　VCMA-MTJ　also　becomes　instable　when　alpha　＜=　0.7.　Furthermore,　the　electrical　model　of　VCMA-MTJ　with　process　deviation　is　also　applied　to　the　R/W　circuit　to　study　the　effect　of　process　deviation　on　the　R/W　error　in　the　circuit.　Considering　the　fact　that　all　of　gamma(tf),　gamma(tox),　and　alpha　follow　Gauss　distribution,　The　3　sigma/mu　is　adopted　to　represent　the　process　deviation,　with　using　Monte　Carlo　simulation,　where　sigma　is　the　standard　deviation,　and　mu　is　the　average　value.　It　is　shown　that　the　write　error　of　the　circuit　goes　up　to　30　%　with　3　sigma/mu　of　0.05　and　the　voltage　(V-b)　of　1.15　V.　At　the　same　time,　the　read　error　of　the　circuit　is　20%　with　3　sigma/mu　of　0.05　and　driving　voltage　(V-dd)　of　0.6　V.　Both　the　read　error　rate　and　the　write　error　rate　of　the　VCMA-MTJ　circuit　increase　as　process　deviation　increases.　It　is　found　that　the　write　error　rate　can　be　effectively　reduced　by　increasing　V-b　and　reducing　the　voltage　pulse　width　(t(pw)).　The　increasing　of　V-dd　is　helpful　in　reducing　the　read　error　rate　effectively.　Our　research　presents　a　useful　guideline　for　designing　and　analyzing　the　VCMA-MTJ　and　VCMA-MTJ　read/write　circuits.