Mars square/opposite Mars: 

In astrology, Mars represents our sexual style. When your Mars squares another person’s Mars, it indicates that your sexual styles are at odds. You express your sexuality in different ways, which can indicate sexual incompatibility. Squares cause friction, so it may be difficult to reconcile these sexual differences.

Your body rhythms may not match well, which can result in disappointment for both of you. For example, Mars in Taurus natives enjoy natural, physical sexual expressions. They are not fond of spontaneity or variety when it comes to love-making. If a Mars in Taurus person partnered up with a Mars in Aquarius person, this may spell trouble.

Mars in Aquarius intellectualizes sex, which may confuse the Mars in Taurus person. Mars in Aquarius seeks plenty of variety in sex, and tends to enjoy the “idea” of sex more than the act itself. This would obviously be a problem for sensual Mars in Taurus, who needs plenty of physical contact to be satisfied. 

The opposition is not as problematic as the square, but the sexual differences remain.

Mars also represents action and aggressiveness. This aspect indicates that you express your assertiveness in different ways. You may spend a lot of time arguing over whose way is best, but this is useless. At least one of you might try to boss the other around, which can lead to arguments and even physical violence. 

You both tend to be self-centered, aggressive, and impulsive around each other. Competitiveness is high with this placement, as well. You tend to irritate and annoy one another, and know how to get under each other’s skin.

Mars trine or sextile Mars 

I cannot stress the importance of having compatible Mars signs, when it comes to great sex! When two peoples’ Mars planets are in harmonious aspects to each other, your sexual energies match well. You like the same things sexually, and it is easy to please one another. Things just feel “natural” with this person.

This aspect also indicates mutual cooperation. You energize each other, and there is a friendly competition between the two of you.

 Mars conjunct Mars 

The conjunction can go either way. While this aspect does not indicate discordant sexual styles, it does tend to increase aggression. Indeed, the two of you are likely to react impulsively or assertively to one another, which can certainly lead to heated arguments and physical violence.

Your sexual styles are very similar, as are your interests in physical activities. This aspect indicates the two of you are competitive with each other, but make sure this doesn’t get out of hand. Either way, you truly energize one another, and are very sexually attracted to one another.